RB25Det Nissan Terrano
Moderator: Mark
Re: RB25Det Nissan Terrano
Also check all your earths thoroughly...I filled all the cylinders and exhaust on my bike in about 30 seconds with a crook earth...well....i forgot to reconnect it
Re: RB25Det Nissan Terrano
Hey thanks for that information just had confirmation from megasquirt guy who also said that was normal...So only explanation is i must of been turning CAS over with fuel pump still hooked up...opps truck is getting the better of me i must admit.
I did look into ECUS similar to those and it was definatly a good option but megasquirt is a very good system if your willing to learn about it..My mate has a RB30DE (non turbo) that is putting out over 300hp and never had a drama, and the beuty is they can be simply adjusted when new components are installed. (i know most ecus can).
My megasquirt came with a tune that was done on a rb25det neo running very similar setup to me standard injectors 3' exhaust right though so i have a fairly good base tune...That other rb that the dyno tune was putting out 260hp at the wheels on 6psi boost...All that is changed is i got him to run mine slightly richer for saftey reasons until i can get the truck down to tauranga to get tuned.
I did look into ECUS similar to those and it was definatly a good option but megasquirt is a very good system if your willing to learn about it..My mate has a RB30DE (non turbo) that is putting out over 300hp and never had a drama, and the beuty is they can be simply adjusted when new components are installed. (i know most ecus can).
My megasquirt came with a tune that was done on a rb25det neo running very similar setup to me standard injectors 3' exhaust right though so i have a fairly good base tune...That other rb that the dyno tune was putting out 260hp at the wheels on 6psi boost...All that is changed is i got him to run mine slightly richer for saftey reasons until i can get the truck down to tauranga to get tuned.
Re: RB25Det Nissan Terrano
IGNORE THIS POST
This information is simplified for those that do not understand the fuel system, sorry to others as it may be boring information, but either way this will stop engine working.
The fuel pump problem i had which was fuel pump “ON” engine would die has been playing on my mind so have a few hours investigation and few simple calculations i have come to a verdict, this simple yet crucial issue cannot be over looked.
So very basic the fuel system works as so on my setup
FUEL TANK (PUMP)-> FUEL FEED LINE-> FUEL FILTER-> FUEL DAMPER-> INJECTORS starting at rear (6) This is half the circuit obviously. So up to this stage the fuel pump is unregulated pressuring around 65psi + through the entire system.
Second half of circuit INJECTORS-> FUEL PRESSURE REGULATOR-> FUEL RETURN LINE-> TANK-> FUEL TANK BREATHER (not fuel just tank air pressure)
So what happens is the fuel pressure regulator is set for 35psi with vacuum or 40psi without, this is what the fuel pressure at idle needs to be at the INJECTORS on an RB25DET.
Once that fuel pressure is reached the fuel pressure regulator opens and starts to return fuel back to tank to keep that desired pressure at INJECTORS (works like a waste gate). This is where the problem begins.
The FUEL RETURN LINE releases pressured fuel back into tank and this pressure should be getting released from the tank vent but on a diesel it is only feed from the diesel pump up front therefore it never had 65psi plus getting pushed through the setup. So in other words the tank is pressurising.
The tank breather is linked to the diffs and transmission and finishes up on the firewall with the half loop of piping.
This information is simplified for those that do not understand the fuel system, sorry to others as it may be boring information, but either way this will stop engine working.
The fuel pump problem i had which was fuel pump “ON” engine would die has been playing on my mind so have a few hours investigation and few simple calculations i have come to a verdict, this simple yet crucial issue cannot be over looked.
So very basic the fuel system works as so on my setup
FUEL TANK (PUMP)-> FUEL FEED LINE-> FUEL FILTER-> FUEL DAMPER-> INJECTORS starting at rear (6) This is half the circuit obviously. So up to this stage the fuel pump is unregulated pressuring around 65psi + through the entire system.
Second half of circuit INJECTORS-> FUEL PRESSURE REGULATOR-> FUEL RETURN LINE-> TANK-> FUEL TANK BREATHER (not fuel just tank air pressure)
So what happens is the fuel pressure regulator is set for 35psi with vacuum or 40psi without, this is what the fuel pressure at idle needs to be at the INJECTORS on an RB25DET.
Once that fuel pressure is reached the fuel pressure regulator opens and starts to return fuel back to tank to keep that desired pressure at INJECTORS (works like a waste gate). This is where the problem begins.
The FUEL RETURN LINE releases pressured fuel back into tank and this pressure should be getting released from the tank vent but on a diesel it is only feed from the diesel pump up front therefore it never had 65psi plus getting pushed through the setup. So in other words the tank is pressurising.
The tank breather is linked to the diffs and transmission and finishes up on the firewall with the half loop of piping.
Last edited by Paulballz on Sun Oct 28, 2012 6:39 pm, edited 1 time in total.
Re: RB25Det Nissan Terrano
Cheers for that info, i guess the same applies to putting in any petrol into a diesel car?
I imagine if i were to do a conversion i would have gotten stuck lol.
Is there any way you could get the setup off a rb25 skyline? that way it would be close to factory?
I imagine if i were to do a conversion i would have gotten stuck lol.
Is there any way you could get the setup off a rb25 skyline? that way it would be close to factory?
Re: RB25Det Nissan Terrano
no problem at all, i have not managed to find any diagrams off a skyline but i would imagine it would be setup different as cars are not designed to travel through water therefore some have diff breathers ect right above the diff.
My 300zx is setup like this and water upto sills will full the diff with water.
I am not sure of the flowing capacity of the petrol terrano fuel pump or how the fuel system is designed but surely they run the same setup as the diesel yet dont have a problem.
When looking way back at my fuel pump setup picture you will notice the diesel return line runs to the bottom of the tank beside the fuel pump, on the RB the fuel return line releases back to the top of the tank and drips down into the fuel. I have had to cut my return pipe so it does the same and drips down into the fuel.
Injectors are nearly done and adjustable fuel pressure reg here this week, all going well i may be able to take the old girl for a spin depending on how it runs and how the auto behaves.
My 300zx is setup like this and water upto sills will full the diff with water.
I am not sure of the flowing capacity of the petrol terrano fuel pump or how the fuel system is designed but surely they run the same setup as the diesel yet dont have a problem.
When looking way back at my fuel pump setup picture you will notice the diesel return line runs to the bottom of the tank beside the fuel pump, on the RB the fuel return line releases back to the top of the tank and drips down into the fuel. I have had to cut my return pipe so it does the same and drips down into the fuel.
Injectors are nearly done and adjustable fuel pressure reg here this week, all going well i may be able to take the old girl for a spin depending on how it runs and how the auto behaves.
Re: RB25Det Nissan Terrano
Paulballz wrote:This information is simplified for those that do not understand the fuel system, etc
It shouldn't. The amount of fuel returning to the tank is either equal to (engine not running) or less than (engine running) the amount being drawn from the tank. It won't pressurize. It will take a little while to drain off 40 psi of air through the vent if you are blowing it into the tank with a compressor tho...
My bike runs a 193lph walbro pump into/out of a 20ltr tank with a 1 or 2mm vent hole. It doesn't pressurize.
Open the fuel cap and run it and see if it makes a difference, that'll tell ya for sure.
Re: RB25Det Nissan Terrano
yeah and the pump is feeding 60+psi which then the injectors take their share and release anything over 40psi back through return line, but if fuel tank is not venting that builds back pressure and holds more pressure in the circuit.. when my fuel pump is on and i unwind fuel cap i get a decent hiss of pressure release, therefore the vent is not sufficent enough and is back pressuring
Re: RB25Det Nissan Terrano
I don't think thats possible, the only way you can pressurise something is either add air/fluid to it or decrease the overall volume. Put a pressure gauge on your fuel rail and measure the pressure, it should be 40psi. The return line should be zero or there abouts.
Re: RB25Det Nissan Terrano
churchill wrote:I don't think thats possible, the only way you can pressurise something is either add air/fluid to it or decrease the overall volume. Put a pressure gauge on your fuel rail and measure the pressure, it should be 40psi. The return line should be zero or there abouts.
That's what I was getting at. Run it without the cap on, see if it makes a difference.
Re: RB25Det Nissan Terrano
Been giving this thing a bit of thought...
A couple of q's first.
Do you have a pressure gauge on it? Or have one to test it with?
Does it do it with the engine running, or just when you're testing it?
Process of elimination.
Try it with the fuel cap off, easy, do that first.
If it's still the same, pull the return line off the fpr, and run it into a large fuel container (or if you got a real long bit of hose into the filler) and try running it like that. It'll take a few minutes to fill the container, it should be enough to see if that fixes it or not. If not, look at the fpr.
If it's cured, then reconnect the return and pull it off at the tank, again run 'er into a container and try again. If it's sorted there too, then the problem is in the return to the tank. if it isn't, it's in the line.
A couple of q's first.
Do you have a pressure gauge on it? Or have one to test it with?
Does it do it with the engine running, or just when you're testing it?
Process of elimination.
Try it with the fuel cap off, easy, do that first.
If it's still the same, pull the return line off the fpr, and run it into a large fuel container (or if you got a real long bit of hose into the filler) and try running it like that. It'll take a few minutes to fill the container, it should be enough to see if that fixes it or not. If not, look at the fpr.
If it's cured, then reconnect the return and pull it off at the tank, again run 'er into a container and try again. If it's sorted there too, then the problem is in the return to the tank. if it isn't, it's in the line.
Re: RB25Det Nissan Terrano
LMFAO, you're taking the piss right pallballz?
Thats one of the most brilliant posts Ive read for awhile
If not, then I am legitimately concerned
Thats one of the most brilliant posts Ive read for awhile
If not, then I am legitimately concerned
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Gardengnome
- Truck Hore
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- Joined: Tue Jul 17, 2012 10:26 am
- Location: Christchurch
Re: RB25Det Nissan Terrano
The cycle of the fuel
1. Pump removes fuel from tank and feeds fuel rail.
2. injectors inject fuel and engine eats it.
3. Remaining fuel is put back in tank.
Assuming you have a closed system, ie no tank venting, and a constant tank volume then look at it from a volume point of view, ignore pressure.
As DEATH_INC mentioned the volume returning is equal to or less than removed. Then either will happen....
1. the same voume of fuel will return = no pressure change due to same volume of fuel and same volume of air.
2. less fuel returns = less tank pressure as the same total volume has less fuel but still the same amount of air. Air will decrease in pressure to take up or accomodate the loss in fuel
If you must focus on pressure, the regulator releases fuel at a preditermined pressure. But that is just a pressure to release, at nothing more. The pressure after the regulator will equalize with the tank and the volume of the tank and return lines. It will not sustain the pressure the regulator regulates at.
1. Pump removes fuel from tank and feeds fuel rail.
2. injectors inject fuel and engine eats it.
3. Remaining fuel is put back in tank.
Assuming you have a closed system, ie no tank venting, and a constant tank volume then look at it from a volume point of view, ignore pressure.
As DEATH_INC mentioned the volume returning is equal to or less than removed. Then either will happen....
1. the same voume of fuel will return = no pressure change due to same volume of fuel and same volume of air.
2. less fuel returns = less tank pressure as the same total volume has less fuel but still the same amount of air. Air will decrease in pressure to take up or accomodate the loss in fuel
If you must focus on pressure, the regulator releases fuel at a preditermined pressure. But that is just a pressure to release, at nothing more. The pressure after the regulator will equalize with the tank and the volume of the tank and return lines. It will not sustain the pressure the regulator regulates at.
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Gardengnome
- Truck Hore
- Posts: 96
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- Location: Christchurch
Re: RB25Det Nissan Terrano
Damn, Forgot one other thing.
If you are getting a hiss from releasing the cap it's more than likely air venting INTO the tank due to the consumption of fuel.
I have seen plastic outboard fuel tanks collapse when the venting valve has not been opened. they eventually starve the engine of fuel.
If you are getting a hiss from releasing the cap it's more than likely air venting INTO the tank due to the consumption of fuel.
I have seen plastic outboard fuel tanks collapse when the venting valve has not been opened. they eventually starve the engine of fuel.
Re: RB25Det Nissan Terrano
Gardengnome wrote:Damn, Forgot one other thing.
If you are getting a hiss from releasing the cap it's more than likely air venting INTO the tank due to the consumption of fuel.
I have seen plastic outboard fuel tanks collapse when the venting valve has not been opened. they eventually starve the engine of fuel.
My Terrano (Td27) makes a small hiss when you pull the cap, always has, it's pretty normal I think...
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Gardengnome
- Truck Hore
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- Location: Christchurch
Re: RB25Det Nissan Terrano
Most cars I've owned have done the same. Especially if you fill right up and then run it almost bone dry. Makes a nice snake noise
Re: RB25Det Nissan Terrano
Is it possible to run a bigger return line? I would imagine the return line should be larger than the supply line (like the oil supplies for turbos).
Maybe the volume is restricting the flow and creating back pressure. Another large line outside the body to the filler/container just to prove its not an issue with the return.
My two cents worth and all worthless no doubt.
Maybe the volume is restricting the flow and creating back pressure. Another large line outside the body to the filler/container just to prove its not an issue with the return.
My two cents worth and all worthless no doubt.
Re: RB25Det Nissan Terrano
Well where do i start,
The truck has my finances at a stale mate at the moment which is i hate been so close to finish.
Heres the verdict some good news and bad.
Yesterday i managed to get the truck to run real well with the megasquirt, it was starting first pop and sounded amazing, but the problem was this was still with the fuel pump turned "OFF" fu*&en strange i know it has had me buggered. As soon as the fuel pump is switched on the engine dies.
It run amazing for around 5 min with no fuel pump then truck developed a "miss" and started "hunting".
This fuel problem has costed a arm and a leg to try and sort with no luck yet
Work done
*Injectors full service, spray tested ect
*Adjustable fuel pressure reg
*Full set of expensive spark plugs (bad move)
*Full strip and clean of fuel rail
Elimination work done
*Ran pump from bucket of fuel to see if it was electrically affecting truck
*Checked fuel pressure and reg over and over it is bang on recommended setting
*Earthed and powered pump it with external battery
*Fuel return flowing well once set pressure reached
Note: during all this we did discover the truck would run but very poor if we turned fuel pressure down to 2 psi so this told us it is definitely a pressure problem not an electrical problem. At this stage myself and the megatuner are very stumped how an engine runs with the fuel pump off as he said a 2500cc engine would die within seconds of pump been switched off. Possibly because of the slow decrease in fuel pressure when pump is switched off but even still it should empty rail fast.
Today megatuner contacted me and said that my MAP setting my be wrong on the ECU (came pre tuned) which would indicate the engine is pumping full fuel in as if it was "100% open throttle". This has lead us to believe that with the correct fuel pressure (Pump "ON")it is flooding the plugs as it is pumping full fuel on idle but not the required air, but with next to no pressure it isnt able to pump fuel as needed therefore minimal fuel which is allowing enough to run.
Pulled all my plug out to find the strangest of things, one of my new plugs is broken clean in half (if this was from me putting it in i would of noticed when i put on coil pack). The other thing i noticed was a sure sign of over fueling (attached picture).
So the fuel mystery continues for now
Exciting information
During the engine running window i got yesterday i managed to put the old girl in drive and go up the drive way just low revs. This has shown me the td27 torque converter has worked!!! it did not stall the engine as feared.
Second
, but most important peice of news is while putting up the drive way my auto run! it didnt go into limp mode (as told by many and read in the re4r01a manual). It selected 2nd then 3rd very smooth and overdrive function worked.
This fuel problem also proved to me (like most of you tryed to tell me) that the vent was not the issue as expected...
I would also like to take the time to appreciate all the support from everyone here it has been a very very testing project that has pushed my capabilitys (an patience, relationship, finances to name a few )beyond anything i could of imagined... at the beginning i thought getting the engine in was going to be difficult, it was a breeze compared to the electrical teething problems...its the support that keeps me focused on the overall goal... 3800+ views with 106 replys.
An Heath your two cents is the same as my thoughts, that is exactly what i thought was happening but turns out it wasnt. The fuel return is a larger dia hose than feed. I thought it was the back presure causing all the greif..Joys of process of elimination
After reading through my last post about the fuel system in a better state of mind (not sleep deprived) i can admit that my mind and train of thought had wondered dramatically to come to that conclusion (bang head against wall)...Just shows how much of a head f*** little problems can be, they lead me to come up with alsorts of ideas
The truck has my finances at a stale mate at the moment which is i hate been so close to finish.
Heres the verdict some good news and bad.
Yesterday i managed to get the truck to run real well with the megasquirt, it was starting first pop and sounded amazing, but the problem was this was still with the fuel pump turned "OFF" fu*&en strange i know it has had me buggered. As soon as the fuel pump is switched on the engine dies.
It run amazing for around 5 min with no fuel pump then truck developed a "miss" and started "hunting".
This fuel problem has costed a arm and a leg to try and sort with no luck yet
Work done
*Injectors full service, spray tested ect
*Adjustable fuel pressure reg
*Full set of expensive spark plugs (bad move)
*Full strip and clean of fuel rail
Elimination work done
*Ran pump from bucket of fuel to see if it was electrically affecting truck
*Checked fuel pressure and reg over and over it is bang on recommended setting
*Earthed and powered pump it with external battery
*Fuel return flowing well once set pressure reached
Note: during all this we did discover the truck would run but very poor if we turned fuel pressure down to 2 psi so this told us it is definitely a pressure problem not an electrical problem. At this stage myself and the megatuner are very stumped how an engine runs with the fuel pump off as he said a 2500cc engine would die within seconds of pump been switched off. Possibly because of the slow decrease in fuel pressure when pump is switched off but even still it should empty rail fast.
Today megatuner contacted me and said that my MAP setting my be wrong on the ECU (came pre tuned) which would indicate the engine is pumping full fuel in as if it was "100% open throttle". This has lead us to believe that with the correct fuel pressure (Pump "ON")it is flooding the plugs as it is pumping full fuel on idle but not the required air, but with next to no pressure it isnt able to pump fuel as needed therefore minimal fuel which is allowing enough to run.
Pulled all my plug out to find the strangest of things, one of my new plugs is broken clean in half (if this was from me putting it in i would of noticed when i put on coil pack). The other thing i noticed was a sure sign of over fueling (attached picture).
So the fuel mystery continues for now
Exciting information
During the engine running window i got yesterday i managed to put the old girl in drive and go up the drive way just low revs. This has shown me the td27 torque converter has worked!!! it did not stall the engine as feared.
Second
, but most important peice of news is while putting up the drive way my auto run! it didnt go into limp mode (as told by many and read in the re4r01a manual). It selected 2nd then 3rd very smooth and overdrive function worked.This fuel problem also proved to me (like most of you tryed to tell me) that the vent was not the issue as expected...
I would also like to take the time to appreciate all the support from everyone here it has been a very very testing project that has pushed my capabilitys (an patience, relationship, finances to name a few
)beyond anything i could of imagined... at the beginning i thought getting the engine in was going to be difficult, it was a breeze compared to the electrical teething problems...its the support that keeps me focused on the overall goal... 3800+ views with 106 replys. An Heath your two cents is the same as my thoughts, that is exactly what i thought was happening but turns out it wasnt. The fuel return is a larger dia hose than feed. I thought it was the back presure causing all the greif..Joys of process of elimination
After reading through my last post about the fuel system in a better state of mind (not sleep deprived) i can admit that my mind and train of thought had wondered dramatically to come to that conclusion (bang head against wall)...Just shows how much of a head f*** little problems can be, they lead me to come up with alsorts of ideas
- Attachments
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- New plugs for sale :)
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Re: RB25Det Nissan Terrano
Paulballz wrote:Well where do i start,
The truck has my finances at a stale mate at the moment which is i hate been so close to finish.
Heres the verdict some good news and bad.
Yesterday i managed to get the truck to run real well with the megasquirt, it was starting first pop and sounded amazing, but the problem was this was still with the fuel pump turned "OFF" fu*&en strange i know it has had me buggered. As soon as the fuel pump is switched on the engine dies.
It run amazing for around 5 min with no fuel pump then truck developed a "miss" and started "hunting".
Do you want to keep going?
First make sure the pump is turning off and on like it should. It should run for a few seconds when the key is turned on, then start again when you crank the engine. The ecu usually turns the earth on and off (I think...) double check that. If you aren't already run it through it's own relay (get one from ripco or somewhere).
Without enough fuel pressure it should really not run for more than a few seconds.
Does the megasquirt have an internal map sensor? Or is it supplied with one? If not, what are you using?
I'll find some info if I can on it and see if I can find an answer for you.
Re: RB25Det Nissan Terrano
Always going to carry on for as long as i can.
The pump is hard wired on a switch, i check the fuel reg gauge every time i turn key to confirm pressure 35psi vac, 45 without....raises at a 1:1 ratio with boost.
Correct about the fuel pressure, when the pump is shut off it does hold the pressure quite well before it slowly creeps down.. But in saying that the engine was running with 0psi reading on pressure reg. (HOW CAN THIS BE????) it must have one hell of a draw and since injectors both strokes maybe it is drawing fuel?
The megasquirt has a internal sensor, it has a vacuum hose that runs to plenium after the throttle body. This is the norm for megasquirt. Talking with the megatuner today and he said that when megasquirt is cranking MAP gauge reads around 95kpa but once fired it should drop to around 30-45kpa, i did not get this to start today and failed to check when engine was running, if it does not drop than as i mentioned the ECU is telling injectors to spray 100%
The pump is hard wired on a switch, i check the fuel reg gauge every time i turn key to confirm pressure 35psi vac, 45 without....raises at a 1:1 ratio with boost.
Correct about the fuel pressure, when the pump is shut off it does hold the pressure quite well before it slowly creeps down.. But in saying that the engine was running with 0psi reading on pressure reg. (HOW CAN THIS BE????) it must have one hell of a draw and since injectors both strokes maybe it is drawing fuel?
The megasquirt has a internal sensor, it has a vacuum hose that runs to plenium after the throttle body. This is the norm for megasquirt. Talking with the megatuner today and he said that when megasquirt is cranking MAP gauge reads around 95kpa but once fired it should drop to around 30-45kpa, i did not get this to start today and failed to check when engine was running, if it does not drop than as i mentioned the ECU is telling injectors to spray 100%
Re: RB25Det Nissan Terrano
Sweet.Paulballz wrote:Always going to carry on for as long as i can.
The pump is hard wired on a switch, i check the fuel reg gauge every time i turn key to confirm pressure 35psi vac, 45 without....raises at a 1:1 ratio with boost.
The pump operates the same, the ecu earths it (through a relay). The other wire should go through your switch to power.Paulballz wrote:If you are meaning the injectors then yes. they spray "open" when the ecu grounds them, they also have a 12v power from a relay.
It cannot. The injectors NEED some pressure to spray.Paulballz wrote:Correct about the fuel pressure, when the pump is shut off it does hold the pressure quite well before it slowly creeps down.. But in saying that the engine was running with 0psi reading on pressure reg. (HOW CAN THIS BE????) it must have one hell of a draw and since injectors both strokes maybe it is drawing fuel?
Partly correct. The info I found says it is an internal map, is the switch on the ecu set to the correct setting for the internal map? It should run a mixed mode, using both the tps and map to supply the correct amount of fuel (not completely sure of this, ask the megasquirt guy) under vacuum. It should switch to map only after it makes boost. The pressure will also drop if you wind it over with the throttle closed, so easyish to check. At 95kpa and no throttle it'll supply too much fuel, but not 100%. In case you hadn't figured it out already 95kpa is atmospheric pressure.Paulballz wrote:The megasquirt has a internal sensor i believe, it has a vacuum hose that runs to plenium after the throttle body. This is the norm for megasquirt. Talking with the megatuner today and he said that when megasquirt is cranking MAP gauge reads around 95kpa but once fired it should drop to around 30-45kpa, i did not get this to start today and failed to check when engine was running, if it does not drop than as i mentioned the ECU is telling injectors to spray 100%
See how those things check out. Also if you can, wind it over and see what rpm the ecu says it's turning.
Re: RB25Det Nissan Terrano
DEATH_INC wrote: In case you hadn't figured it out already 95kpa is atmospheric pressure.
not quite atmospheric pressure is actually 101.3kpa
Re: RB25Det Nissan Terrano
keithal wrote:DEATH_INC wrote: In case you hadn't figured it out already 95kpa is atmospheric pressure.
not quite atmospheric pressure is actually 101.3kpa
Yeh...I found that, just didn't really consider it that important at this point...it's close enough.
Edit: Doh....you're onto it, it runs a small amount of vacuum when you crank it. Paul, check it both cranking and not...those are the two pressures you're looking for...
Re: RB25Det Nissan Terrano
Yes the pump is meant to run the same but i have hard wired it as suggested from mega tuner.
"It cannot. The injectors NEED some pressure to spray".
The fuel pump wires are disconnected, the fuel pressure reg flciks (must be injectors opening) then reads "0psi" the engine runs...Tell me im missing something??? or any suggestion on how this is possible? i checked the hose uncase they happened to be another pump from diesel..it is direct line from pump to fuel filter, fuel damper, rail, injectors, FPR then tank... No pump, no pressure.
That video from previous post showed engine reving also all with the pump switched "OFF"
"Partly correct. The info I found says it is an internal map, is the switch on the ecu set to the correct setting for the internal map? It should run a mixed mode, using both the tps and map to supply the correct amount of fuel (not completely sure of this, ask the megasquirt guy) under vacuum. It should switch to map only after it makes boost. The pressure will also drop if you wind it over with the throttle closed, so easyish to check. At 95kpa and no throttle it'll supply too much fuel, but not 100%. In case you hadn't figured it out already 95kpa is atmospheric pressure."
Ok the ecu is pre set with tune straight from identical (rb25det neo) running engine. That engine had same setup as mine. Stanard coilpacks, injectors, ect. I will confirm this though with megasquirt.
It cranks at around 250 - 300RPM. Here is a video of the megatuner while cranking my engine.
http://www.youtube.com/watch?v=zhEHnk_8XFk&feature=plcp
Please note the pulse width / duty cycle was dropping off during this video that is why vid was made as i sent it to tuner...That problem is now sorted so please ignore those gauges, However the MAP / Spark Advance / Coolant temp and engine rpm are all working in this video... The engine timing has been set at 20 BTDC. My engine does not have a manifold air temp and have been told from megasquirt tuner that the sensors are not need neither is the O2 sensor for megasquirt. Apparently the o2 sensor is stuffed after 80ks anyway and needs to be wide band sensor (dont know what this means so i just agree)
"It cannot. The injectors NEED some pressure to spray".
The fuel pump wires are disconnected, the fuel pressure reg flciks (must be injectors opening) then reads "0psi" the engine runs...Tell me im missing something??? or any suggestion on how this is possible? i checked the hose uncase they happened to be another pump from diesel..it is direct line from pump to fuel filter, fuel damper, rail, injectors, FPR then tank... No pump, no pressure.
That video from previous post showed engine reving also all with the pump switched "OFF"
"Partly correct. The info I found says it is an internal map, is the switch on the ecu set to the correct setting for the internal map? It should run a mixed mode, using both the tps and map to supply the correct amount of fuel (not completely sure of this, ask the megasquirt guy) under vacuum. It should switch to map only after it makes boost. The pressure will also drop if you wind it over with the throttle closed, so easyish to check. At 95kpa and no throttle it'll supply too much fuel, but not 100%. In case you hadn't figured it out already 95kpa is atmospheric pressure."
Ok the ecu is pre set with tune straight from identical (rb25det neo) running engine. That engine had same setup as mine. Stanard coilpacks, injectors, ect. I will confirm this though with megasquirt.
It cranks at around 250 - 300RPM. Here is a video of the megatuner while cranking my engine.
http://www.youtube.com/watch?v=zhEHnk_8XFk&feature=plcp
Please note the pulse width / duty cycle was dropping off during this video that is why vid was made as i sent it to tuner...That problem is now sorted so please ignore those gauges, However the MAP / Spark Advance / Coolant temp and engine rpm are all working in this video... The engine timing has been set at 20 BTDC. My engine does not have a manifold air temp and have been told from megasquirt tuner that the sensors are not need neither is the O2 sensor for megasquirt. Apparently the o2 sensor is stuffed after 80ks anyway and needs to be wide band sensor (dont know what this means so i just agree)
Re: RB25Det Nissan Terrano
turoa wrote:LMFAO, you're taking the piss right pallballz?
Thats one of the most brilliant posts Ive read for awhile
If not, then I am legitimately concerned
Haha glad i could entertain ya turoa
, i think ill stick to fitting an welding once this is over Re: RB25Det Nissan Terrano
keithal wrote:DEATH_INC wrote: In case you hadn't figured it out already 95kpa is atmospheric pressure.
not quite atmospheric pressure is actually 101.3kpa
You could tell me its 100101.3kpa an ill still knod my head up and down and say "uh haa, sounds about right"
Re: RB25Det Nissan Terrano
Paulballz wrote:keithal wrote:DEATH_INC wrote: In case you hadn't figured it out already 95kpa is atmospheric pressure.
not quite atmospheric pressure is actually 101.3kpa
You could tell me its 100101.3kpa an ill still knod my head up and down and say "uh haa, sounds about right"
Lol. As long as the megasquirt says it's close to 101 when you turn the key on, and it drops when you crank it without pushing the accelerator it'll be fine.
Re: RB25Det Nissan Terrano
Paulballz wrote:My engine does not have a manifold air temp and have been told from megasquirt tuner that the sensors are not need neither is the O2 sensor for megasquirt. Apparently the o2 sensor is stuffed after 80ks anyway and needs to be wide band sensor (dont know what this means so i just agree)
Probably correct, you def don't need the oxy sensor, but make sure the ecu isn't set in 'closed loop'. Same with the air temp, as long as the ecu isn't looking for a reading it'll be fine without it.
I have no idea why you can get it to run without the pump and with no fuel pressure. Something is very wrong. You need to go over the fuel system again. You fitted the skyline pump into the tank? I'd rewire it like megasquirt recommends too. If it ran in another vehicle it can't be much, you just need to figure out what you've done that's different to the skyline setup...
I'll admit it..I'm a bit stumped by it for now...
Re: RB25Det Nissan Terrano
Paulballz wrote:It cranks at around 250 - 300RPM. Here is a video of the megatuner while cranking my engine.
http://www.youtube.com/watch?v=zhEHnk_8XFk&feature=plcp
Can you do another vid so we can see what it looks like now?
Re: RB25Det Nissan Terrano
DEATH_INC wrote:Paulballz wrote:I have no idea why you can get it to run without the pump and with no fuel pressure. Something is very wrong. You need to go over the fuel system again. You fitted the skyline pump into the tank? I'd rewire it like megasquirt recommends too. If it ran in another vehicle it can't be much, you just need to figure out what you've done that's different to the skyline setup...
I'll admit it..I'm a bit stumped by it for now...
Yup something is seriously different, super fuel effiecent smart engine
Yup will try get the plugs early this week and will get it running and film megatune, with new plugs it will run fine for a while then begin to foul them so will know exactly what is going on with MAP.
Thanks alot for your help you have gave me that bit of hope back that has been destroyed time after time
Re: RB25Det Nissan Terrano
Paulballz wrote:Thanks alot for your help you have gave me that bit of hope back that has been destroyed time after time
I know how frustrating it can be...I've just got My bike with the link in it going...with a very different setup to what it had. I've already killed 2 sets of iridium plugs in it and it's still hardly ride able.
Good luck with it, you'll get there