Help With Gtr

[Dirty32]

Hey all...

Iv been reading the forum for a few months now, only just registered.

Iv read a few threads that seem to be similar, but just wondering if anyone can share any advice.

Im the proud owner of a clean R32 GTR, and it provides much fun and pleasure.

I had a problem with it about a month ago, and only knowing what i know about engines & cars through the magazines and forums i read, so dont be too harsh (im hardly a DIY mechanic).

The problem i had, was that i would accellerate but the car would jerk and not go anywhere. The revs would also not go up so i realised it wasnt a driveline problem, but something to do with my fuel pump / lines or intake / ignition & spark.

I took it to my mechanic (normal ultratune who it is generally serviced by) and he refered me to a EFI specialist.

He told me that i had faulty O2 sensors in my dumps, and that he would replace them as the factory ECU was getting different airflow readings from the AMF's and O2 sensors which was causing the engine to cut the fuel or inject too much (rich and lean etc) which was causing it to hesitate and not accellerate.

Cut a long story short, the EFI specialist charged me nearly $500 for fixing and testing the O2 sensors and to make sure that the engine was running ok. For the first week the car was good as new, but recently it has started again.

I was going to ring him and let him know that he hasnt done the job properly, or is it something else, like coil pack or sparks / fuel pump / faulty or dirty AFM's etc that could be faulty instead of what he has replaced???.

Any feedback would be great, as if im gonna ring him to give him a serve, i wanna be right or at least have some ammo to go with.

Again, im a newbie so be easy.... Has the specialist pulled a fast one and ripped me off????

Cheerz!!!

[blind_elk]

Firstly, AGAIN!, O2 sensors do not play any part in the running of an engine while accelerating. This point cannot be stressed strongly enough.

Now, to the potential solution - how old is the battery? Nissans are EXTREMELY sensitive to voltages. The battery may be in good enough condition to start the engine, but then so much time gets spent re-charging the battery off the alternator that the ECU doesn't get enough voltage and views this as a problem, and starts playing silly-buggers.

Failing that, the ECU may be sensing some sort of "knock" - maybe due to leanout from a failing fuel pump. Under that circumstance, the ECU retards spark which retards power.

[R31Nismoid]

Firstly, dont take the car to ultratune

Second, dont take it to a supposed "EFI specialist"

Both will know nothing, and as you found out, he said O2 sensors which have nothing to do with the problem you describe.

1) Clean AFM's

2) Change plugs

3) Check all CAS/Coil/Ignition connections for corrosion and/or poor connection

4) Check battery age, if old, change it

5) Fuel system - fuel pump/rail pressure. Fuel filter change.

6) Test coil packs - see DIY section fo the how-to

Thats enough to get you started.

Oh, and take it to a performance workshop that specialises in Skylines, or you'll have more problems

[TTT]

Mate the last 3 things you have there is where I would start.

When was the plugs last changed?

When were the AFM’s last cleaned?

Here is a similar problem I had and what I tried…

http://www.skylinesaustralia.com/forums/in...&hl=misfire

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