Rough Idle...???

**TMAN8255** · 01-29-2005 01:58 PM

Whats up,
I have an 03 WRX with like 45K on it and the car runs really good, but it has an idle that seems like it wants to shut off once in a while. The idle will be completely fine and then drop down like it wants to shut off. Has anybody else experienced this , or does anybody have any suggestions. Any help would be greatly appreciated.
The dealer says that I dont need to change the spark plugs until like 60K , but I might want to change the fuel filter. Does this sound right , and is there anything that I can do ( tune up wise ) to make it run smoother???
Thanks
Travis

**Silver04Sti** · 02-10-2005 04:36 PM

I had this issue with my sti and it would actually stall on me as I put the clutch in approaching a stop light. It happened all the time. I actually took it in to Subaru on different occasions and finally they got rid of it by a combo of throttle body/intake sys cleaning and sending the ecu off for a re-flash. I doubt you need the reflash since it was something they did more with the initial 04 sti's. I would start with a can or two of BG44K and then if that doesn't work have the throttle body cleaned. How's your air filter btw?

**Darrell** · 02-11-2005 05:16 AM

The same thing happened on my old Mazda, but it never actually stalled out. The idle would search and search. The problem is usually related to a vacuum leaks somewhere. Check for cracked/missing vacuum hoses. High-pitched noises often accompany vac leaks.

**Trunkmonkey56** · 02-11-2005 05:32 AM

Well, I have an 03 and when it was maybe 6 months old I put a turboback exhaust on. Every now and then when I started it after it had gotten cold the engine would search for idle, runing high in the rpm's and then really low, sometimes to the point of stalling. If you tried to drive while it was doing this, it would jump around in the rpm's making the car lurch, even with perfectly even pedal pressure. It would do that untill boost came in, and then it would be fine on boost. All of that would stop once the car warmed. This would only happen maybe once every two three months. I got Cobb stage 2 management another 6 months down the road, and never had the problem again. This seemed to happen after runing the car hard and then letting it cool as the temps droped at night. Hard to remember for sure though. I bought the car new and never played with anything for that matter except for a short ram intake and the TBE. Intake is off now, but before the downpipe was on, just with the intake and catback, everything ran fine.

**Weedy** · 11-24-2006 07:26 PM

My car is very similar in miles, and approximate year. I have an '02 with 55k miles. It has over the course of the past year or so developed a cold starting issue, where it will hunt for the idle pretty bad. It will either settle down after it has become warm, or it will settle after I shift into gear. I have tried quite a few different things, including the BG 44k. I think I have narrowed it down to the idle control valve. If you do a search on NASIOC I know that you will find plenty of information on how to clean that etc. Maybe take a look at yours, although be sure to have a new gasket ready!