V8 missing at 2krpm

Disco-Blue · Post by **Disco-Blue** » Sun May 20, 2007 12:59 pm

Ok my 3.5 EFI V8 is missing when the engine gets warm at around 2000rpm. I have replaced all of the below and still get the problem which is now really pissing me off after the money ive wasted trying to fix it, any ideas anyone?

Plugs
Leads
Coil
Dizzy Cap
About to do fuel filter

Have checked and cleaned rotor as well.

mercutio · Post by **mercutio** » Sun May 20, 2007 1:07 pm

i was going to say Â¨when i had my land rover V8 whenever i had problems i learnt the first thing to check is the pointsÂ¨

then i noticed yours is efi

wopass · Post by **wopass** » Sun May 20, 2007 1:08 pm

its british..... :roll:

im surprised it revs past 2k

sorry back to the problem at hand, check for a vacume leak or condensation in or near the conection plugs to coils,dizzy. efi and high voltage dont like wet or dirty terminals.

matwelli · Post by **matwelli** » Sun May 20, 2007 1:35 pm

Does it miss at 2K and above , or only at 2k and clears itself higher up ?

Disco-Blue · Post by **Disco-Blue** » Sun May 20, 2007 3:54 pm

matwelli wrote:Does it miss at 2K and above , or only at 2k and clears itself higher up ?

Clears itselfs higher up but then comes back around 2500 - 2800. Only does it on open road and not under load as in actually going off road.

lowbox · Post by **lowbox** » Sun May 20, 2007 6:21 pm

IGNITION AMPLIFIER?

Rangielux · Post by **Rangielux** » Sun May 20, 2007 6:57 pm

wopass wrote:its british..... im surprised it revs past 2k

hey hey, naughty boy :wink:

try and isolate which cyl it is (might narrow things down abit), yeah could be a vacuum leak. you've covered most of the spark side of things but lowbox has a point. The only other things I can think of quickly is a bad injector - dirty or faulty, broken valve spring? (unlikely but who knows)

interesting problem

matwelli · Post by **matwelli** » Sun May 20, 2007 10:35 pm

The fact that it goes away, only happens under light load sort of rules out most of the answers so far (ie mechanical/electrical faults)

Only thoughts are that at 2K to 2K8 rpm, light load on the highway the engine computer will be running things fairly lean, easy for a misfire to take place esp if one injector is a bit gummy, you would not notice under load, but at very lean running with short injector opening times you would notice it.

Do you get the same prob if you free rev it in the driveway ?

If you do, get a mate to hold the throttle at the point that its missing, pull the injector plugs off one at a time, the Cylinder that is missing will have no change when you pull the plug off, pulling it off any of the working cylinders will make the engine change note and drop revs

91Rangie · Post by **91Rangie** » Mon May 21, 2007 4:21 pm

Have you laced the spark plug leads in the correct way?
I dont mean the firering order
With the EFI it is very important that they are as it will cause a misfire

Disco-Blue · Post by **Disco-Blue** » Mon May 21, 2007 10:22 pm

91Rangie wrote:Have you laced the spark plug leads in the correct way?
I dont mean the firering order
With the EFI it is very important that they are as it will cause a misfire

Please explain what lacing means, sorry im not that technical. Also does not misfire when free revving. Am going to replace fuel filter as it probably needs it anyway. Am running 96 in it but could it just be shit petrol? I might try BP's 98 and seeing if it does it on that.

91Rangie · Post by **91Rangie** » Tue May 22, 2007 12:17 am

From the service manual

Fitting H.T Leads
Ensure replacement H.T leads are correctly refitted as illustrated
Failure to observe this instruction may result in cross-firing between two
closely fitted leads which are consecutive in firing order.

Disco-Blue · Post by **Disco-Blue** » Tue May 22, 2007 10:24 am

Pretty sure I have done that but will double check just to be safe.

Disco-Blue · Post by **Disco-Blue** » Wed May 23, 2007 2:51 pm

Ok have checked and all leads are in their rights places, I don't know what it could be and have been trying to solve this for the last 3 months so think I might just get rid of it.

billyvanboheman · Post by **billyvanboheman** » Wed May 23, 2007 3:30 pm

Range Rover, Give ya 50 bucks for it :lol:

Sadam_Husain · Post by **Sadam_Husain** » Wed May 23, 2007 5:20 pm

I'm sure theres lots that will disagree but sometimes its just better off ringing up the local guy that fixes those things and arange to drop it off in the morning and pick it up in the afternoon all running properly again :wink:

It sure beats all those hours spent in the shed late at night chasing your tail and getting nowhere and frustrated

Disco-Blue · Post by **Disco-Blue** » Wed May 23, 2007 7:34 pm

billyvanboheman wrote:Range Rover, Give ya 50 bucks for it

Owch thats a cheap shot, talk about kicking somebody when there down :shock:

billyvanboheman · Post by **billyvanboheman** » Wed May 23, 2007 8:02 pm

Disco-Blue wrote:Owch thats a cheap shot, talk about kicking somebody when there down

I couldn't help it, just way toooooo hard to resist :lol:

Don't despair, I'm sure you will get it, anyone on here work for or know of a mate that works for a Rangie dealer, they may have struck the problem before and be able to work it out from your description.
Stick with it, it will work out!!

Scott · Post by **Scott** » Wed May 23, 2007 9:09 pm

I had a miss with my 1ggeu, turn out to be the water temp senser telling the ecu that the engine was cold thus over fueling and missing

Disco-Blue · Post by **Disco-Blue** » Wed May 23, 2007 10:35 pm

Nah temp gauge works all good so don't think it could be sensor related. Think i'll just tidy it up, sell it and get something else thats not Land Rover.

Petemcc · Post by **Petemcc** » Wed May 23, 2007 10:40 pm

dont give up on it jst yet. really you have only had one problem with it, and you have just replaced alot of bits that were probably about due to be replaced anyway and that you would replace on any new truck you got. take it to a landrover place and see what they think. it cant be anything to serious just a matter of eliminating things it isnt till you find it.

Pete

billyvanboheman · Post by **billyvanboheman** » Wed May 23, 2007 11:11 pm

Are you in CHCH Disco-Blue?

Rangielux · Post by **Rangielux** » Thu May 24, 2007 7:14 am

Disco-Blue wrote:Nah temp gauge works all good so don't think it could be sensor related. Think i'll just tidy it up, sell it and get something else thats not Land Rover.

Ya never know it could be sensor related, more often than not the temp gauge sensor is separate from the ecm temp sensor.
If its overall a good vehicle and you like it still, keep it, sometimes its better the devil you know. It sounds like that $50 part replacement of some kind might fix it?

Sounds like you tried most things at a basic level (no offence) and spent a bit of money on parts already. Take it to a tuning specialist or someone who is an enthusiast rover dude or the Landie/rangie dealer (but sometimes they're not all that ethusiastic but very expensive

)

Canty land rover owners club (if theres one) may have a contact for a good tech guy. - thats assuming you're down that way?

Steve_t647 · Post by **Steve_t647** » Thu May 24, 2007 10:10 am

Summit 4wd on Haseldean Rd do land and range rovers and they advertise on this site.

With the correct gear or experience it could be a 10 minute diagnosis.

I have no idea if you can get the computer panic and log info to a laptop or a display of some sort but being fuel injected the computer will be telling you something.

It was the one saving grace of running a link down the quarter, but link does not have enough fuel and ignition points for smooth road driving (250 rmp increments)

Good luck and they are a really good 4x4 when going well :oops:

I just went for a Hilux to stop hireing trailers

Disco-Blue · Post by **Disco-Blue** » Thu May 24, 2007 12:28 pm

Hmm will try summit 4wd as see if they can work it out, if not will sell it and buy something a little better nad cheaper to run.

Thanks for all your input guys!

JAMUBA · Post by **JAMUBA** » Thu May 24, 2007 12:36 pm

Hi Dude
Is your tacho doing dodgy things, could be an alternator fault, follow this-http://www.rangerovers.net/repairdetails/altrebuild.htm
This site is gold for rover stuff, dont be put off by it being a range rover site, late 80's rrc run mostly the same running gear as a disco 1.
Chris

karmobRob · Post by **karmobRob** » Sun May 27, 2007 8:41 am

Lucas alternators are notorious for bad diodes which can affect the ecu.
Disconnect alt or remove belt and give it a go.
ROBERT

Disco-Blue · Post by **Disco-Blue** » Sat Jun 02, 2007 2:41 pm

Ok have had another play round with it today after finally getting some time to, i disconnected the water sensor as well as trying a piece of wire in each contact but the thing is still missing so it can't be the that.

Alistar from Summit4WD said he would take a look so will be going to see him, if your on here Alistar PM me a mobile number if you can please and I will txt you to find out when suits you.

Cheers

karmobRob · Post by **karmobRob** » Sun Jul 01, 2007 10:59 am

what was the final outcome Blue?

Disco-Blue · Post by **Disco-Blue** » Sun Jul 01, 2007 11:25 am

Sold it haha, bought a cruiser instead.

fweddy · Post by **fweddy** » Sun Jul 01, 2007 11:28 am

Disco-Blue wrote:Sold it haha, bought a cruiser instead.

Well well! Well done!