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

    • So now doing the change and first time dealing with rb so little nervous giving engine power and potential for screwing it up When you align all marks and then remove crank bolt, timing move little I assume you can put the bolt back in once you have removed the pully to get timing to where you want?   here is pic of my both intake and exchust cam aligned, depending on angle you look they seem to be either aligned or a half tooth or so out. Any thoughts? Should you angle your face and look at each mark that way as if looking straight rather than from above as it can be misleading   <a href="https://ibb.co/ZpnhcvbF"><img src="https://i.ibb.co/HfWrGR9b/IMG-4447.jpg" alt="IMG-4447" border="0"></a> <a href="https://ibb.co/4wm2wn4q"><img src="https://i.ibb.co/JWBqWwr1/IMG-4445.jpg" alt="IMG-4445" border="0"></a>   https://ibb.co/ZpnhcvbF https://ibb.co/4wm2wn4q
    • Thanks for the reply @GTSBoy Haven't really thought of that yet, but you are right. If the hose was damaged it should be absolutely pissing by now. I'll put some heat sleeve around it for good measure since I'm already removing the line anyway.  Maybe I'll put on some of the stock hardlines if I ever fully remove the turbos again. Maybe when T51R modding the compressor housings? Might be a fun mod on GT28s for that "fake single turbo" effect.
    • Update 1: I did some work on the car already before finalizing this post and my "issues" list. I dropped the Tomei exhaust in favor of the HKS Hi Power Silent. Sounds nice and I can actually hear myself think now. Also gives me a realistic chance to legally drive without silencer inserts. A bit of cheating was necessary to still be able to mount the Top Secret style diffuser. Some malusage of washers and a bit of "convincing" toward the brackets and exhaust hanger seemed to do the trick. The shaky steering wheel has been resolved as various suspension components were worn, like sway bar bushings and link bars. Most notably the two steering tie rod ends. Had some trouble finding bushings because my sway bars are not OEM thickness, 23.x up front and 27 rear. But non adjustable, so no aftermarket I suppose. Maybe they are nismo units? Turbo oil drain hoses were definitely still the originals and are new now. Wasn't the cause of the turbo oil leak sadly. Currently removing the rear turbo because of it, I suspect the braided oil feed line is the culprit. This issue needs to be dealt with so I can work towards actually getting the turbo setup legal and inspected. Two new issues to add to the list as well. Rear Main seal is probably leaking. Time will show how bad it is, I don't really want to drop the gearbox right now just for the stupid seal. Could fix a few other things in one go once I do that. Front right driveshaft grease is going past the cv boot, so at some point I'll fix that too.
    • Ok so no 4cyl clutch... Yeah it is a factory manual. So if iam correct i need clutch and flywheel too? I can use something that suits something like R32 GTST?   EDIT: https://www.ebay.com/itm/224291042776 Is this ok?   EDIT2: i maybe forget to mention this(dk how important it is) but the trans will be behind RB25DET NEO(iam doing swap) It will be there for a little while. Iam planing to do bigbox or BMW tranny..
    • You're probably right about that one. Thanks for your suggestions, I hope I don't need a new 3rd brake light. Although wiring issues might arguably be worse. Right now I'm in the midst of a turbo removal because of my oil leak, other problems are going to have to wait for now.
×
×
  • Create New...