R32 Gtr Jerking Under Throttle

[Nathyne]

I have an 94 GTR I am having hesitation and loss of power with under throttle. Driving on the highway it would lose all power and slow down then all the sudden have power again.

It will also not rev over 4500 RPM without jerking and RPM jumping around a lot.

I have replaced:

Injectors (have 3000kms on them since replaced)

Spark plugs

one MAFS (was getting a mafs error and replaced one then it cleared)

checked coils all were at 1.2 ohms (was a crappy multimeter the probes had about a .4-.5 resistance)

I am stumped as to what it could be I am running a stock tune with nistune just set for larger injectors.

I am going to look into getting an igniter pack wondering if anyone else had any ideas.

[Nathyne]

Okay so i wrote down what my car was doing as I took it for a drive. Only seems to have problems under full throttle in first gear @ 4500-5000RPM second @ 5500-6000RPM and doesn't seem to have problems in third. So I think it only has problems depending on the load? The EGT (cat sensor or whatever) light did come on when I was having running problems my air fuel ratios are good aswell. Maybe my ecu is retarding the timing?

[GTR-N1]

Welcome to SAU Nathyne - preferably under better circumstances.

Process of elimination...

Plugs tick > 1x AFM tick (but what about the other one?) > Coilpacks tick (but are there any scorch marks even if faint? tried wrapping electrical tape around each one or swapping with someone else's?) > Looms (are they old/stiff/hard/inflexible) > ECU

When you've sorted it out, don't forget this...

http://www.skylinesaustralia.com/forums/R3...ru-t324580.html

...and join up with SAU

All the best.

[blind_elk]

... I am running a stock tune with nistune just set for larger injectors.

"Stock tune" doesn't necessarily suit every car. I would suggest getting it onto a dyno and tuned properly.

[Nathyne]

"Stock tune" doesn't necessarily suit every car. I would suggest getting it onto a dyno and tuned properly.

Fuel ratios are good it ran over 3000kms perfectly on this tune I don't think that's the problem. My car is stock except intake exhaust and the injectors so a "stock tune" should run my car no problems.

[larlok]

Fuel ratios are good it ran over 3000kms perfectly on this tune I don't think that's the problem. My car is stock except intake exhaust and the injectors so a "stock tune" should run my car no problems.

Check Fuel pressure and flow

[Nathyne]

You are correct was just logging on to say it is my fuel pump completely died on me yesterday.

Thanks for the help