r33 cutting out

[-= SKiZO =-]

Hey mate, sorry took me so long to get back to you, been very busy.

Firstly i'm not a mechanic, so my advice I give to you out of experience.

It's not the BOV. If it was it would dip or surge everytime you slowed down hard, causing the engine to stall or come close

to stalling. I've had this problem before on my VL. This is caused by incorrect adjustment or fault of the tension spring in the BOV. I've found it is a common scapegoat of mechanics who don't know where to look. From the way you described it your car just cuts out, and normally the engine moves steady through the rev range and idles steady.

The problem that I had with my GTS-t was this... It would run great except for hot days. Consistently(like every day)after a bit of hard driving/city driving, you would be stopped at the lights or go over a speed hump or turn the corner, whatever and it dies... The idle quickly jumps around for a sec and then dies. Start it again, and a little bit later, it would do it again.

As soon as I read your post I was gonna say 99% sure that it was the AFM. This is what was wrong with my car(worked it out through LONG process of elimination) and apparently this is a VERY common problem on GTS-t's. The thing is, I've read that normally when there is something wrong with the AFM your fuel economy goes as well. This was true for me. Mine was shithouse - Even though the car was running great when cold I would barely hit 300k's to a tank of Optimax. When I fixed the AFM, now I can run 360-380, hard city driving. Everything on my car is stock. Your car does 400k? I think that's pretty good, maybe you have lotsa mods or aftermarket ecu? So that is why I can't say for sure that it is the AFM. Maybe under some faults it actually leans out the mixture rather than enriching it. Someone else here might be able to clear it up for us.

A few other things I noticed with my problem was that when the engine cut out I would try turning over the ignition from the same position the key was in. Chances are it would stall immediately. If I turned the ignition completely off and tried starting again. It would start fine immediately and run roughly for the time being. Some sort of reset thing happens with a number of things including the AFM when you do that. Next time it happens, look out for this.

So what I would try...

Reset you ECU - just for fun.

Try the ECU diagnostic - does it come up with anything. Just a point, when I did the diag, it didn't give any faults, even though it is meant to report AFM faults. My problem was DEFINITELY the AFM cause when I pulled it apart the connections were obviously dodgy.

Do you keep your car regularly serviced? When you rev it steady and free rev it, is it smooth or does the engine sound like a V8? If it sounds like a V8 check spark plugs > fuel filter > coil packs > injectors in that order.

It might be sludge/crap in your throttlebody - it would affect or jam the idle speed motor, but unlikely to jam it only when it's hot. Can't hurt to look. Take off that rubber thing around the throttle intake, and run your finger inside. Should be only mildly dirty. If it's filthy and got chunks of grease in it. Then you got bigger problems. If your bored, pull apart the idle speed motor and give it a bath. Again unlikely - but check for vacuum leaks/loose connections.

The reason why i'm saying to check these things first is that, if you do pull apart the AFM, it will involve soldering to put it back together. It's not hard but, i'm not sure how comfortable you would be with that.

Anyway, i hope the problem goes away by itself, otherwise let us know how you go. Feel free to ask me to clarify things if you need(hope I wasn't too obscure). :burnout: