R33 Gtst Cutting Out Intermittantly

[JackVGX3.0]

Hey guys. After searching unsuccessfully I'm starting a post for the first time in a long time.

I've got a S1 '94 R33 GTST, got 197xxx km's, have had for about 3 years. Haven't had any issues apart from a clutch up until around 3 months ago when it started being a real bitch. Left it over the weekend, around 2-3 days of no driving, just sitting outside. Jumped in to go somewhere, started up, stalled immediately. Got it going after a few repeats of this problem, got over it, fine, okay, moving on.

Since then, it's started to cut out when coming to a stop at lights etc. Not often, usually kicks back up with a hit of the key. But not too long after, it's now cutting out whilst driving, whether it's cruising, under load, under boost, whatever. It will sometimes cut out completely (take it out of gear and the engine will stall) and cut back in a second later or sometimes I'm having to pull over and switch the ignition off and re-start the engine to get it to come back to life. I cannot for the life of me replicate any scenario that causes it to cut, it's completely random.

I'm a mechanic by trade and this is completely doing my head in cause I'm struggling to diagnose the issue. I've put it on scan tools to check the OBD and it's not registering any fault codes in the ECU at all.

So. Anyone had similar issues? If so, what was the cause?

I'm due to do a timing belt within the month and was thinking of replacing the CAS but I don't want to spend $400+ on a new sensor and find the problem hasn't gone away.

Help much appreciated.

[scotty nm35]

Most likely the AFM is the cause. Cut the lid open and re-solder the dry joints on the connector pins.

[JackVGX3.0]

I work with a company who specialise in repairing PCB's and instruments. I'll take it there. Thanks man. I'll bump to let you know how it goes.

Namiss gauges and instruments - Newcastle NSW. Good people.

[scotty nm35]

No worries. There is a 'howto' on here somewhere.

[r33 gtst 300ponies]

yeah mate download the manual and check all your sensors starting with afm and shake it to see if connector/connections are no good, you may need to reset the computer if you touch somethings but a multimeter will check most things

[r33 gtst 300ponies]

and check fuel system pump pressure and pinch return line to put up the pressure to see that cures it if so injectors are dirty

[JackVGX3.0]

Bit of a late update.

Pulled AFM out, got the PCB inspected and resoldered, threw it back in, driving home from work it shit the gear completely, went into rich mode hard and wouldn't rev above 2500 rpm. So obviously AFM shit itself. Replaced with remanufactured unit and all good.

Now, when getting into it, full boot and around 4500-5000 rpm it hesitates a bit. Computer re-adjusting fuel maps? Timing (I just did a timing belt the day after replacing AFM, but did it to the letter from the manual)?

[onboost33]

I have had a similar problem, my 33 GTST was cutting out spitting and coughing when under load (even felt like boost leak and wasnt getting as much psi), my AFM was ok, I replaced fuel pump and still had the problem, had a pressure test done and there was a hairline crack in a hose, the hose that goes to IAC valve (Idle Air Control) and it runs like a dream! sounds like a similar situation JackVGX3.0 im not saying this hose is your problem but might pay to check it out!!