Hey guys my 07 wrx TR has a flutter motion in the rpms. It will idle normally then spike up to bout 1500rpm then drop to about 100rpm. Yesterday it did it at the mall to the point where my car actually shut off.... What can it be? Dirty throttle body? A sensor? Car has almost 60k miles On it.

 

Is there a check engine light? Any mods? First thing I'd check is the MAF. If it's dirty, carefully clean it with some MAF cleaner NOT carb spray/brake cleaner and allow it to fully dry before trying to start your car. The other thing I'd check is the IAC. Hope this helps.

 

There is no check engine light no mods to the engine and I thought it was my MAF because it was dirty but I cleaned nice and good and my car still does it :/

 

vacuum leak?

 

Sounds like either vacuum or Idle Air Control Valve that sits right on top of the throttle body.

 

Thanks for the info guys!

 

this.



check all of your inlet/tmic hoses.


and everyone always should clean their maf.

 

My MAF has 105K miles. Never needed to be cleaned.

 

can't tell if trolling....

 

The OP may need to clean their MAF sensor but the statement that everyone should always clean it isn't true.

Helpful info about leaks (so I don't look like a troll):

If there is a vacuum leak the engine will consume more air than it measures at the MAF sensor. This results in a lean condition. Closed loop ECU fueling will compensate with a positive fuel correction. This positive fuel crorrection will be a clue there is a leak.

If there is a leak and the engine is making boost and the trim goes negative the leak is between the turbo and the heads. If the trim remains positive (while under boost) the leak is between the MAF sensor and the turbo.

Either way I'd go to a professional. FW-MS or a dealer. IF there are mods I would not go to a dealer. If you go to FW tell Paul DP sent you for a discount on a reach around.