[ArchangelF16]

I'm having some issues with my scoobie stalling. When I'm coming to a stop, off throttle with either the clutch in or in neutral, sometimes the RPM will fall all the way to 0. The idle isn't lumpy, but it will occasionally jump from the normal ~600 to somewhere closer to 1100rpm, then drop back down again. It's an 06 WRX stage 2 pro-tune with 95k miles. I thought it could be spark plugs (which I replaced with NGK ir back at 60k miles), but according to the manual it isn't due til 120k. I also replaced the oil on schedule and still have the same problem.

I should also note that the serpentine belt snapped recently when the pulley locked up. The tech replaced the harmonic balancer, pulley, belt, and pulley crankshaft. Would this have anything to do with it?

 

[SD_GR]

There is no serpentine belt, and it is debatable whether there is a harmonic balancer. I also don't know what a pulley crankshaft is. However, all that leads me to suspect that the crank and/or cam angle sensors might have been struck or jarred, and they are worth checking, as is the IACV provided your car is not drive-by-wire (and thus lacking one).

 

[ArchangelF16]

here's what broke. The car has been at my parents' house for the past 3 years while I've been in Japan. The belt snapped when my dad was driving.

 

[SD_GR]

OK got it, delete the image now for privacy. Will post back.
SD

 

[SD_GR]

OK so the A/C pulley seized, and they replaced that, and also the crank shaft pulley and the A/C belt. Now your car is stalling. I think I'll go with my initial reaction: check crank and cam angle sensors. Also suspect they knocked something when doing the work, either a sensor harness or a vacuum line. No CEL?

 

[ArchangelF16]

No CEL idiot light at all. Would it throw a code without the light (assuming it's not burned out?)

 

[teflon_jones]

Yes you can have codes without a CEL. Do you have an OBDII reader? If not, go to an auto parts store and you can get it read for free.

 

[SD_GR]

If car builds boost ok suspect sensor. If boost low suspect leak and/or FPR connection. Guessing at this stage, diagnosis in person would stretch my "abilities" (I use the term loosely) so remotely I'm at wit's end. Bump
For more help. SD

 

[ArchangelF16]

hooked up the AP and no CEL codes. Still stumped.