Cylinder Not Running On Idle? R32 Gtr

[bilaldabab]

Hi Guys,

I have a problem at idle with my GTR, cylinder number 5 is not running when idleing or not under load, When the engine get some load, it kicks back in and runs fine with plenty of power. I have replaced all 6 spark plugs, i have swapped over the coil packs with others and its not a coil pack issue. However when i Unplug the plug to the 5th coilpack, the revs don't change/drop. So I'm guessing it has something to do with the plug/wiring?

Anyone got any advice before i start replacing everything?

I recently replaced the whole engine and got it tuned. This started happening a day after i got it tuned. Took it back to the mechanics who installed the motor and they couldnt find the problem...

Any help would be greatly appreciated!

[MillsyR33]

VAC LEAK??

DO YOU HAVE OR HAVE ACCESS TO A SMOKE MACHINE??

[bilaldabab]

No i dont unfortunately

[MagicMikeZ32]

May or may not be wiring.

If #5 isn't contributing at idle anyway, cutting fuel or spark to it won't change revs.

[GTRNUR]

Swap your number 1 and 5 coil packs and see if the problem moves. If it does you know where your problem is.

Next, run the engine with the number 5 coil pack out of the head, and with a spare plug in it, sitting on top of the motor and watch for spark. If there is no spark, then its wiring or ignitor.

If there is spark you need to eliminate fuel. Swap the number 5 and 1 injectors and see if the problem moves. If it does, then injector. If not, then potentially wiring or ECU issue.

Borrow a stock /replacement ECU from someone and see how it goes. Have your tuned map uploaded if need be.

[DVS JEZ]

Sounds like it could be a blown intake gasket on that cylinder. Get some brake cleaner or wd40 etc and while the car is idling spray around cylinder 5 inlet, throttle gasket and injector oring etc. see if the idle changes

[bilaldabab]

Swap your number 1 and 5 coil packs and see if the problem moves. If it does you know where your problem is.

Next, run the engine with the number 5 coil pack out of the head, and with a spare plug in it, sitting on top of the motor and watch for spark. If there is no spark, then its wiring or ignitor.

If there is spark you need to eliminate fuel. Swap the number 5 and 1 injectors and see if the problem moves. If it does, then injector. If not, then potentially wiring or ECU issue.

Borrow a stock /replacement ECU from someone and see how it goes. Have your tuned map uploaded if need be.

I have tried swapping my number 1 and number 5 coil packs and it made no change.

I will try the rest when I get a chance this week. Thanks for the info, will let you know how I go!!

[bilaldabab]

Sorry forgot to mention, also when its a cold start, the revs drop quite a bit and struggles to stay on (turns off most of the time), i need to keep my foot on the accelerator for about 15-20 seconds before it stays on..

[bilaldabab]

So i tried spraying some throttle body cleaner on the injectors earlier, the revs did not change on injectors 1, 2 and 3. however the revs went higher by 100-200 rpm.. when sprayed on injectors 4, 5 and 6.... when i sprayed it on all 3 at once, the revs jumped upto 500 rpm.

Does this mean the intake gasket is leaking towards the back? Could this be the issue or is this an entirely new issue?

[niZmO_Man]

Gasket it sounds like. Checked the bolts/nuts?

[DVS JEZ]

Yes sounds like the inlet gasket is blown. Its pretty common to happen as the gasket gets old. I normally replace the inlet and throttle gaskets with a set of metal nitto gaskets. Also check all the hoses under the plenum as they may need replacing while the plenum is out

[bilaldabab]

Awesome thanks for the reply guys.. Is it hard to replace yourself? do you know of any DIY guides?

[SargeRX8]

Is that the gasket from runners to head? Shouldn't be hard. I think the rb25 plenum to runners is probably the ugliest job to do. I did it without a guide but there should be something readily available. Google change rb26 plenum gasket or intake gasket.

[DVS JEZ]

Its a veryfun job to do on RB26's. willtake atkeast 3hours to get off, then cleaning of old gaskets and replacing hoses etc. then atleast 3hours to get back on.

DO NOT CLEAN IN AND AROUND THE THROTTLE BODY BUTTERFLIES!!!

[MagicMikeZ32]

LOL 3 hrs to get intake gasket off. And they say vg's are hard to work on... Could have my engine out in less time than that

Edited June 25, 2013 by MagicMikeZ32

[SargeRX8]

f**k sounds like a PITA of a job. I can imagine bruised knuckles would come into play here too.

[DVS JEZ]

Yes definately not fun. Its definately easier with the engine out haha

[bilaldabab]

Ended up being the intake manifold gasket. got it fixed for $200 which i thought is worth it.. Thanks for the responses!!!

[Ben C34]

200 is a bargain for that job! 6hrs labour... Was that mates rates?

[500hp]

Injector mate