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Hi All,

I have a problem with my 2002 NB where the engine cuts out at around 5000 to 6000 RPM and restarts when revs fall to around 4000 RPM.

The first time it happened was at a Speed Off The Streets day at Wakefield. I just assumed I had hit the rev limiter, so I lifted the foot momentarily then planted it and all was good and it didn't happen again that day. Then at successive track days it started happening at lower revs and more frequently and the engine would not restart unless I changed up a gear. Then the petrol pump failed. So, "aha" I thought, this has simply been a symptom of a failing petrol pump and after changing the pump, expected that the problem would be solved. Alas, no. At the next track day the only way I could stop the engine cutting out was to limit the revs to around 5200 RPM.

The problem hadn't ever happened on the road, in hind sight, because I never rev higher than about 5000 RPM in normal driving. So yesterday I took the car out to see if I could replicate the problem on the road. I went to a quiet country back road where I could drive a bit erratically and not be a danger to any one while I did a few runs. I found that it didn't matter how hard I accelerated, or which gear I was in, the engine would cut out between about 5000 to 6000 RPM and if I kept my foot on the accelerator and just let the car slow, it would restart at around 4000 RPM. Finally I did a test in neutral. I parked the car and then slowly raised the revs. At around 6500 the engine cut out. I left my foot on the accelerator while the engine slowed down. Then at 4000 RPM it restarted, revved up to 6500 and cut out again. I let this happen a few times just to see that it was consistent. At no time during all this did the Check Engine light come on.

Then I drove home. The engine starts, hot or cold, idles and runs fine... below 5000RPM. The car is standard, other than suspension mods.

Anyone able to suggest a fix, or can anyone recommend a good mechanic/auto electrician around Wollongong?

Thanks.

Cam or crank sensor probably. Maybe Fuel pump.

Maybe fuel filter.

Does it still dropout if you take it very slowly up to 6500, and stays out till 4000?
Also do you have any aftermarket engine parts (ECU, injectors, fuel pump, etc)?

Cheers,
Ken.

Hi All,

Thanks for your posts.

The problem appears to have been fixed. Following your suggestions, NitroDann, I checked out the crank sensor first because it was easier to examine than the cam sensor. I found the air gap between the sensor and the sensor plate was more than 2 mm when it should be between 0.5 to 1.5 mm. So I reset it to 0.5 mm and then did the rev test in neutral. When that was successful I drove out to test it on the road, and joy of joys, no cutting out. Such a simple fix. Thanks for the advice.