Over the past few weeks I've noticed my car seems very rough at idle, mostly when sitting at a light or stopsign. I know it's tough to describe something like this but basically it feels "chunky" almost like I've put in a cam. Any ideas what could be causing it? It's a 95 TA with about 30,000 Miles on it.

Edit: The only mods I have on it are SLP CAI, SLP Loudmouth exhaust (took out the cat) and 3.73's. It doesn't seem rough any other time though, and pulls through the powerband like normal, but at a stoplight it just feels very very rough and shaking.

 

Tons of things could possibly be wrong....check plugs, wires, O2 sensors, etc....

Is it rough only at idle or does it feel a little "off" throughout the powerband? Is it bad through the rpm's but fine at WOT?

 

The car seems fine every other time but at idle it just seems very rough. Still pulls really strong all the way through the powerband...

 

bad iac can cause it.

 

See my post Also same problem but when it stumbles the idle can jump up to 1,000 rpm. I did all the cleanouts and now it seems a bit smoother. I will give it a little time & see how it runs after a few days. If still present I will need to have someone do some diagnostics for the IAC. I have done the wires, plugs, o2 sensors within the past 2 years so I will need to narrow it down to other things at this time , (Coil, opti, injectors, vac leaks,map, etc) I have a Haynes manual & it does give some good info for these components. Oh yea I also seafoamed the car last year.

 

can be a shorted area in either.