FIXED: Stuttering at 3k RPM.. has anyone figured this out? --- VIDEO INSIDE

[Ryann]

^PM'd.

[Zba]

If you have the original chip could you swap it back in? I've had chips on my VWs crap out on me.

[Nairb]

I don't have another chip, unfortunately.. car had a Dinan chip when I purchased the car, which I sold after replacing it with a MarkD 93 chip.

[mr ilia]

I was going to say to try stock "175" chip, as well AFM.
Try borrowing the another chip somewhere or buy "performance chip" from ebay for about 30.00.

[immajackuup]

op what cat-back you have?? sound pretty nice.

[Nairb]

Doesn't really start hard when initially starting.. probably revs to like 2k and then falls.. no CEL at all and no codes thrown during a stomp test.

IMMAJACKUP.. no idea what exhaust setup it is.. PO put it on.

[Nairb]

Ok so.. still have not been able to figure this out unfortunately. The car is now hitting a wall at 5k hot or cold.

I replaced the AFM, tried a new DME with stock chip (thanks Ryann) and also checked the connection for my o2 sensor.

I have not replaced my crank position sensor.. maybe that could be the culprit?

[siazul]

Was gonna say AFM but I guess Id be wrong, had similar issue a couple of months ago and changing it out with an extra I had fixed it. Maybe you need to clean the ICV?

[Nairb]

Cleaned the ICV a couple months ago.. also, my idle is solid.. would an ICV effect high-revs?

[Leo_328i]

Ok so.. still have not been able to figure this out unfortunately. The car is now hitting a wall at 5k hot or cold.

I replaced the AFM, tried a new DME with stock chip (thanks Ryann) and also checked the connection for my o2 sensor.

I have not replaced my crank position sensor.. maybe that could be the culprit?

If you've tried DME and AFM then crank sensor sounds legit.

Perhaps the crank sensor is faulty is is making the ECU think to activate the rev limiter. In the video the tacho needle doesn't bounce off at 5000rpm it kinda goes all over the place for a bit. So perhaps at that engine speed the crank sensor isn't able to send a signal that the DME can understand and then the DME freaks out and activates the rev limiter.

That seems to make sense to me.

[Dj Buttchug]

not sure if stock motronic is limited rev-wise

[Nairb]

I just want to say, this is like a fucking curse. Right when the powerband kicks in the engine stutters and you either have to shift or let off the gas.. I want to keep my m42 but my patience is wearing thin.

Any way, thanks for all you peeps trying to help me figure this out. I am definitely going to keep posted.. if anyone has any more suggestions, please feel free to give me some insight!

[mr ilia]

I will say again, this is either AFM or the DME chip. I have stock "175" chip I can let you borrow. I also have a spare AFM, only for borrowing. If you pay shipping I can send it over....it will Comming from Canada so duties/taxes may have to be paid at the border.

[Nairb]

...I have replaced the AFM and I swapped out the ENTIRE DME which had a stock chip. Neither of them helped my problem.. (see post #22)

[Nairb]

Ok, I am having another hunch here.. could it possibly be the fuel pump? I just really don't think it is the crankshaft sensor.. there are no other symptoms, and the car runs BEAUTIFULLY up until 4500-5000 RPM.

Could the fuel pump be dying and not sending enough fuel/maintaining pressure for higher revs?

I have not replaced the fuel pump in this car yet, not sure how old it is.