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I'm having a problem with my car.

Problem: The car cuts out while driving, just gets no power for about half a second and then kicks back in (at any revs, any gear, any speed), and when at idle, sometimes stalls.

The car: RB25DE from R32, manual transmission.

I've read a few things saying it 'might' be the AFM, but is there really any way to check?

The problem is so intermittent, that sometimes for a day or two the problem won't occur. I drove out this morning and it stalled I think 5 times. Stopped for a minute, and on the way back (15-20min drive) it didn't do it once.

What are some solutions to exactly diagnosing this problem? Should I go to someone who tunes RB25's? I don't care about spending some money, as long as I can definitely determine the problem.

Thanks,

-Jimmy.

Edited by -Jimmy-
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check all your vaccum lines in your engine bay too see if they've split cracked, usually they are pretty worn out in r32's being how old the little gems are

check for exhaust leaks (cracks in exhaust, ie on exhaust manifold where it gets really hot)

clean afm sensor with AFM/MAF cleaner (repco sells it)

other than that cant think of anything else at the moment

After doing what was recommended above, (check vacuum lines, and clean AFM etc.)

Sounds like the AFM has given up the ghost. Replace the AFM with a new one (or second hand one) from a mate and see how it runs. If it fixes the problem, buy one and your done.

If it doesn't fix it, then you need to check the fault codes on the ECU. This might tell ya what is wrong. From experience, the symptoms you describe is usually the AFM.

Good luck!

its not a engine fault, ive just reconditioned my engine COMPLETELY except for fan belts and this happened to me a week ago. The car cut out for probably 3 second and i hit the accelerator 2 times and it didn't do anything and then it just turned back on when it went from 80km\h down to 50km\h. Engine felt like it was still running as if i had the clutch held in.

I asked mechanic and its an electrical fault. Relays and fuse's have to be checked and even the ECU can be playing up in worst case's.

If it were a piece of piping it would be noticeable all the time as there would be lover revs due to pressure loss.

To check your AFM just disconnect and see if it runs differently. If its the same as before then you will want to change your AFM, however if it runs sh*ter than before, then its not:)

Edited by alex1991s

I took out the fuel filter and drained it and noticed that it was VERY dark and dirty, sediments of dirt in there. Perhaps I got dirty fuel one time? Anyway, so far so good, my car hasn't played up since I filled up with fresh fuel and changed the filter to a brand new one.

I'll be changing and checking this more regularly from now on.

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