Jump to content
SAU Community

Recommended Posts

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!

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.

  • Like 1

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

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!!

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..

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?

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

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.

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!!!

  • 2 weeks later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Thanks guys,  Yeah I should at least have them dynoed, at least then I know what I've got as a starting point.  The springs on these are hard as rocks. I vaguely remember Russman saying he was going to sell the shocks to me with the rocks fitted, as he was keeping the softer springs for his new setup.  I didn't click at the time but of course that was to let me know the shock/spring wouldn't be matched.  I also remember pricing up new springs around 2014-15, but, house, money etc. it never happened. So that was another reason to have them rebuilt. I have rebuilt the forks on many motorcycles so I think I could handle the seals on these easily enough, but getting the valving right would be a rabbit hole I cbf exploring.  Duncan, interesting to hear RP was tuning these back then. I might give them a call.  In the mean time I have been busy fitting sway bars. The Whiteline rear sway bar I purchased 15 years ago finally got fitted, along with the Whiteline front bar that showed up last week. Just waiting on new links for the front sway bar to finish that off.  And my spare set of advan AVS VS5's should be back from the powder coaters in a Pearl White finish sometime this week, with a set of Hankook RS4's lined up for fitting.  And then I just have all the suspension bushes to do. A comprehensive kit is on the way... Lots to do before the Ararat hill climb. Cheers guys 🍻   
    • Nice car! I’m glad folks in the US have gotten past the FnF and are buying real cool cars like the 260RS I was with a bunch of mates in Portland about a year ago and spotted a green Stagea (just a regular 2.5T AWD) parked about 2 blocks away and they were like “a what?” So I made a bet with them for a round of beers and said “ok one of you run down there and tell me if the steering wheel is on the correct side” 5 mins later the American comes trudging back up the hill and goes “he’s right guys. Ok what beer do you want?”
    • Should replace OR drop the tank, give it's good clean. Might be worth replacing that entire fuel level/pump/cradle thing with this: https://frenchysperformancegarage.com/products/fpg-s13-180sx-r32gtst-single-pump-hanger-kit-billet-hat-6-v3-fpg-089?gQT=2  
    • Thank you so much for the help
    • Yes it is ATF. I quote @Duncan "it takes a good synthentic auto trans fluid like Castrol Transmax Z" It's not a diff. It's a transfer case. Totally different thing. Yes, fluid will come out the sender hole. No you do not really need to drain it. Just pull the old, quickly poke the new, clean up and top up. But realistically, you should probably take the opportunity to change it anyway.
×
×
  • Create New...