WANTED Surf V6 InTank Fuel Pump

wjw · Post by **wjw** » Wed Feb 07, 2007 7:23 am

Hi all,

After a Surf V6 Intank Fuel Pump urgently, anyone know where I could find one lurking about?

Cheers,

Bill

SupraLux · Post by **SupraLux** » Wed Feb 07, 2007 3:21 pm

Whats up with the pump you're running?

wjw · Post by **wjw** » Wed Feb 07, 2007 6:44 pm

The original 2JZ fuel pump is driven by an ECU that controls fuel flow (high and low) . The Fuel ECU is also hooked into the ECM. We had a supra with a 2JZ sat in the workshop next to mine and went through all the diagnostics stuff and the only difference between the two, were the readings from the fuel system.

The commodore pump can't keep up at full flow, which isn't suprising from what I've read about them. Also I think the idling problem is caused by not having the fuel ECU and controllable flow. When at idle the fuel flow should be low, so the theory is its overfueling, because if you add more air it idles properly.

thoughts?

Madaz · Post by **Madaz** » Wed Feb 07, 2007 8:51 pm

I dont know that the fuel pump would be causing your problems at idle especially with efi where there should be no way it can over fuel because its only injecting what the computer tells it too.
I would be looking at the idle control valve or some other idle controlling sensor or possibly just a simple vacume leak.
You might be right about the commodore pump though, at the weekend I built and installed a surge tank in my 1-uz hilux using the commodore pump to fill the surge tank and a 400hp Bosch pump to the engine
I cant believe the difference in the way the engine behaves now.
I would recomend you talk to Phil if you cant get you idle sorted.

Cheers

(and good luck!)

Madaz · Post by **Madaz** » Wed Feb 07, 2007 9:14 pm

Forgot to ask?

Did you put the oxygen sensors back in you exhaust?
Also you might find that because the computer has been disconected for some time that it has reverted to its base settings and if you drive it for a bit it will sort itself out , this is how a 1uz computer apparently works

wjw · Post by **wjw** » Thu Feb 08, 2007 7:15 am

We've tested all the sensors, the idle control, TPS, Speed Sensor, etc. I've done about 400km's in it so computer is well run in. If I want to keep the commie pump, I'll need to move it as they aren't designed to suck

Rik has the same problem with the 2JZ in his truck and the only difference between our two trucks and a standard supra is the Fuel ECU and Fuel Pump. Hence us pointing at that.

The V6 pump is an EFI model and is basically the same as the supra pump, but will bolt straight into my Prado tank.

SupraLux · Post by **SupraLux** » Thu Feb 08, 2007 8:49 am

Following that information logically, I would think at idle that the fuel pressure could possibly be too high at idle, so that even though the injectors are only opening for a preset time the fuel being injected might be more than in a Supra where the fuel control (do they have a separate ECU, or is it just a relay controlled by the main ECU to run the pump at 1/2 voltage, thus reducing flow), causing it to run rich and rough...

try putting the fuel pump on a 6V supply and see how it idles... that should confirm or eliminate this as a problem.

Steve

wjw · Post by **wjw** » Thu Feb 08, 2007 10:49 am

SupraLux wrote:Following that information logically, I would think at idle that the fuel pressure could possibly be too high at idle, so that even though the injectors are only opening for a preset time the fuel being injected might be more than in a Supra where the fuel control (do they have a separate ECU, or is it just a relay controlled by the main ECU to run the pump at 1/2 voltage, thus reducing flow), causing it to run rich and rough...

try putting the fuel pump on a 6V supply and see how it idles... that should confirm or eliminate this as a problem.

Steve

ok this is what the manual says:

DTC 78 Fuel Pump Control Circuit
CIRCUIT DESCRIPTION
The fuel pump speed is controlled at 2 steps (high speed, low speed) by the condition of the engine (starting,
light load, heavy load), when the engine starts (STA ON), the engine control module sends a Hi signal (battery
positive voltage) to the fuel pump ECU (FPC terminal).
The fuel pump ECU then outputs Hi voltage (battery positive voltage) to the fuel pump so that the fuel pump
operates at high speed.
After the engine starts, during idling or light loads, the engine control module outputs a Low signal (about 9 V)
to the fuel pump ECU, the fuel pump ECU outputs Lo battery voltage (about 9 V) to the fuel pump and causes
the fuel pump to operate at low speed.
If the intake air volume increases (high engine load), the engine control module sends a Hi signal to the fuel
pump ECU and causes the fuel pump to operate at high speed.

We have tried lower fuel pressure at idle, works when hot, not when cold.

Madaz · Post by **Madaz** » Thu Feb 08, 2007 12:06 pm

What kind of commodore pump are you using?
Im a little confused by "not designed to suck" comment in your earlier post.
I presume your using a inline VL pump?

wjw · Post by **wjw** » Thu Feb 08, 2007 12:43 pm

Madaz wrote:What kind of commodore pump are you using?
Im a little confused by "not designed to suck" comment in your earlier post.
I presume your using a inline VL pump?

Yes and from what I've read on the US Supra forums, the VL Pumps aren't good for Supras. The only way to use them is to have a header tank, otherwise they can't pump enough fuel.

Also just did some reading, the Oxygen Sensor only exists on California Spec vehicles.

Mattman · Post by **Mattman** » Thu Feb 08, 2007 4:06 pm

The newer 1UZFE's have a variable speed fuel pump driven by an ECU so there is no return line off the injection system.

Without a regulator or return line then the pressure will continue to increase and the increased pressure will cause the injectors to over supply fuel as the injection sequence is based on time open at a known pressure.

You could fit a manual regulator and return line and then run whatever pump you like.

Most EFI pumps don't tend to like sucking. In tank systems are definitely the way to go.

Matt.

wjw · Post by **wjw** » Thu Feb 08, 2007 4:09 pm

Mattman wrote:Most EFI pumps don't tend to like sucking. In tank systems are definitely the way to go.

Thats what I was told, hence the hunt for a V6 surf pump as they are EFI. Found one at a price! or I just have to wait for this coaster to get off his ass and get it out of his surf... three weeks and counting

Mattman · Post by **Mattman** » Thu Feb 08, 2007 4:10 pm

The pumps are hard to find and the wreckers want big $$$ for them for some reason.

Do you have the wiring down to the tank for the pump already or do you need to run some?

Matt.

wjw · Post by **wjw** » Thu Feb 08, 2007 8:50 pm

Mattman wrote:The pumps are hard to find and the wreckers want big $$$ for them for some reason.

Do you have the wiring down to the tank for the pump already or do you need to run some?

Matt.

If we can't use the existing pump wiring, we'll only be about 2ft short with the existing VL pump wiring.

Will get one this weekend hopefully.

Once I've got that I just need to solder a new socket onto the ECU as we dont have a plug

worzel · Post by **worzel** » Fri Feb 09, 2007 8:54 am

just rang Mark at Lineside but i think you must have rang him as he said someone rang him for one for a conversion job and is going to pick it up

Kev

wjw · Post by **wjw** » Fri Feb 09, 2007 10:53 am

worzel wrote:just rang Mark at Lineside but i think you must have rang him as he said someone rang him for one for a conversion job and is going to pick it up

Kev

I've given Mark my name now ;-)

Macca · Post by **Macca** » Sun Feb 11, 2007 10:34 pm

Hi, Havent looked on here fora while. I have a V6 petrol in tank pump you could have for cheap. am scrapping a lotof parts, will list them in classifieds first i think.

wjw · Post by **wjw** » Mon Feb 12, 2007 7:16 am

Cool, I have one now, but I could do with a spare

wjw · Post by **wjw** » Tue Feb 13, 2007 2:08 pm

Well, we took the tank out last night and it won't fit... so the three people who told us it would are wrong... bah! So now I have a V6 pump for sale.

SupraLux · Post by **SupraLux** » Wed Feb 14, 2007 3:46 pm

Just sit it in the tank and see if its going to fix the problem... if it doesn't then it doesn't matter anyway... if it does, look to fit a tank from something else under the truck... V6 bighorns have a rear-mounted tank with an in-tank pump... maybe you could make one of those fit?

Steve

wjw · Post by **wjw** » Wed Feb 14, 2007 7:31 pm

The V8 Prado Ricks doing has an expensive external pump on the way, so we are going to test the theory with that. Will cost us nothing but time :-)