I have a 03 wrx and yesterday my car started to hesitate and while I'm at a light. It stalls and it seems like it could be my fuel pump or fuel filter? Maybe plugs or coil packs? I have iradium IX not too long ago. Maybe I have to replace them again? I had a cel for my front o2 sensor but just got that replaced today. I thought that was the problem but now cel is gone and nothing changed. I'm thinking Im also having a head problem cause when I reach 5k rpm or higher, it has a knocking sound or loose metal ish sound. I don't think its my heat shield. Any ideas what my problem is? I'm not driving it around for now until I have everything fixed.

 

what's the mileage on ur car?

 

118xxx

 

@ the light does it rev up and then die out by itself?

 

I had the same problem with my DSM......Cam Angle Sensor was bad.

 

i replaced my idle/air control valve sensor and it never did that again.

 

^
I'd do the same. Just swap that sensor with ur Suby buddy and see if there is any difference

 

Nice thanks. So idle air control valve sensor ? Sorry to newb out but where would that be and how would I do it?

 

when you pop ur hood is that little sensor on the top of the manifold

 

Well ive decided to get change my up pipe and recheck all my vacuum tubes. I've recently bought an sti catless up so removes one of the sensor. Hopefully that fixes something and if not then ill be considering the idle air control sensor

 

wtf is wrong!?! runs way better, no pinging noise or rattle ish noise or loose metal noise after 5k, but a little rough idle. sometimes it seems like its about to stall while im at idle but runs good. and cel throws a P0172 (bank 1) system too rich.... help?

 

Ssseeeeeaaaaaafffooooooaaaammmm!!!

 

^ I had the same problem. I was driving from So. Cal up north and my car just turned off by itself on the free-way while I was going 60mpg. Needless to say I was hit from behind. Never did find out what caused that, but then again it's never been repeated.