Why Is My Gtr Acting Like Windows

[Helious]

Hey everyone,

I've got a rather random problem with my GTR that is random is the sence is happens randomly, but annoying non the less.

Basically the fuel cut is activating at around 2800 RPM, which is most probably just before the Turbos start to spool. I've had this problem since i brought it but has only happened on 2 occasions prior to this.

I use BP ultimate, stock ECU and only an aftermarket FMIC and pods.

Could this be related to my Coil packs or a faulty connection between the AFM and ECU, or is it something more annoying like the internal wastegate. But again is doesnt happen very often and when it doesnt my car runs perfectly.

Cheers

[Bullet32]

Are you sure that its the fuel cut?

I would start with the process of elimination technique...

Try replacing your O2 sensor first and check that you AFM isnt filthy dirty (check the little wire inside the actual AFM housing, spray with electronics parts cleaner, or carbie cleaner).

Check that your crank angle sensor is still working, you'll need to borrow someone elses for this...

Then check coils, plugs etc.

Other than that Im not sure what it could be.

[RB- ajsx]

do you have an aftermarket fuel pump?

[Amaru]

Check all vacuum lines and intercooler piping for any leaks or loose clamps. As its starting to build positive boost pressure it may be blowing open a small leak.

Clean the AFM as suggested above, o2 sensor I wouldnt worry about too much (as mine ran fine for years without) and also check the o-rings on the injectors (the problem that elluded me for 6 months).

[BNR32t]

useless input:

Run bill gates down... Then the car should be fine.

[race_snooze]

fuel pump!!! maybe check pressures

[Helious]

Well today it worked fine and then while i was driving it started up again and when i was driving back from CIT it just stopped when I was at a set of lights. It is very random but I do recall the guy i brought them off saying the coils will require replacing sooner down the trace as they are getting worn or whatever they do in their old age. I've checked the intercooler piping when I put the plumback pipe on and they seem fine. I'll give the AFMs a clean and the actual connectors, as I think this might be the problem if not the coils. But I'll do everything that has been mentioned as it could be one of those aswell.

CHEERS!

[Bullet32]

If your coils need replacing then they will most likely be cracked due to the plastic they're made from cracking, causing the spark to "arc" (jump out the side rather than travel down through the spark plug), but Ive never heard of it being so bad that it actually cut the engine, it usually just causes it to run really rough.

I would be checking the fuel pump if I were you, sounds like its cutting in and out intermittently.

[OZR32GTR]

I had what sounds like the same problem, and it was one of my air flow meters. I just had some z32's put in so i've got 2 stockies that you can borrow to test if you need. Only problem is that I'm away with work work for another week, if you want them then just PM me.

Cheers,

Brad

[Helious]

Hey, I'm giving the AFMs a clean right now. I not sure if the fuel pump is to blame as it cuts at the same spot everytime and not at a random time. I'm thinking the ECU isnt letting the REV range go above when the turbos start to spool as it thinks there isnt enough air to run them efficently, that if it is the AFMs.

See how the clean goes. If it still having a problem, I might have to borrow yours for a test Brad.

THANKS!

[RB- ajsx]

had this problem when i installed a bosch 040 fuel pump. around 3000RPM it'd splutter n surge. not always, but every now and then. check the pressure just to be sure.

[SUKA]

Hey, I'm giving the AFMs a clean right now. I not sure if the fuel pump is to blame as it cuts at the same spot everytime and not at a random time. I'm thinking the ECU isnt letting the REV range go above when the turbos start to spool as it thinks there isnt enough air to run them efficently, that if it is the AFMs.

See how the clean goes. If it still having a problem, I might have to borrow yours for a test Brad.

THANKS!

hi mate, it stuart swing your car past work and we will plug your car into my scan tool and see if it comes up with any codes.

[Helious]

Gave it a drive today and didnt have the problem, but judging from the past it has to be problem free for 2 weeks before I say the problem is resolved...On a more stupid note my other cars battery went flat while i was driving home...in the dark...oh why are the headlights dimming and why does my Revometer show Zero while in going 60...lol maybe my alternator carked it i dunno. But I'll be dropping in my GTR to ya soon Stuart as I'm getting the roadwortthy do at PW aswell as my CV boot issues. But it would be nice to see if anything else isnt right with my GTR.

I also found out one of my pods is half crushed...Those Apexi ones arent really that cheap are they ><

[Helious]

Hey ya!

I think the AFM clean fixed the problem as it has been going good for 2 days now and ive noticed it a bit more responsive.

Thanks for all your help but if it appears again its back to the list of elimination.

CHEERS!!

P.S. You get muck with my honda civic on monday Stuart, alternator is either dead or near enough to it.

[widebody32]

A/f meters are a common thing on these cars,if it happens again i would try borrowing some as the symptons you have are what you will get when an air flow meter goes.

[Helious]

Nah, the whole fuel cut problem is fixed now...but another problem which was probably being hidden by the preveous has started. Basically I remember reading something that may be about it and they described it as 'engine sounds like a subaru engine' So basically is runs rather rough at times and has no power and at other times its completly fine and then it goes back. I could be acceleration it rather aggresivly and still be as slow as my other car. I might take up Suka's offer and take it down to his work and get it computer checked.

Cheers!

[Helious]

OMFG... My car is now swapping between two problems. On its that one of the coil packs decided to work or not on a day to day basis and the other is still the same problem I had before. I had the AFMs tested and they are both giving the same constant reading so one isnt broken. Its on and off and even stops while im driving and i know this and the cars revs drop a little and then its fine. I think my car is cursed as the fuel meter decided to work or not...its working now but before it was at rest position (sitting on the little plastic thing to stop it moving more down) and before that it just sat on quater of a tank even if the tank was full. Ive had a diagnostic on the engine and it said nothing was wrong. Grrr, it going to check the O rings on the injectors and think about who can check the fuel pump pressure, but chances are when i book it in the car will be running fine. Maybe i have to get an inline fuel pressure gauge to see if it is unusually low. And maybe a ECU reset just for the fun of it.

CHEERS!

[race_snooze]

Go see John at Trojan motorsport. The money your spending on finding the problem could be spent and to find and resolve it in a very short time.

Edited October 18, 2007 by race_snooze