2002 GT30 Idle problem

[Guest]

Hi All,

Just bought my second Sub, first was an 03 GT Legacy (single turbo), now on a 2002 GT30- Man the non-turbo is a great way to go!!.

I had the car imported for me and it drives wickedly, except for an idle issue.

At times the revs will shoot from 500rpm to 1100rpm for no reason at all, or when a big load comes on (engine fan, headlights etc). This sometimes also causes the car to stall when the revs drop back down from 1000-1100rpm or even at times when driving when relaesing the throttle after a quick full throttle acceleration.

The importers have had the computer test done to check for any faults and none were registered, so Its been serviced, new plugs fitted and injector cleaner run through it but the problem is still there.

Any thoughts on where to check next would be greatly appreciated!

[Guest]

remove and clean the idle control motor on the throttlebody with subaru upper engine cleaner. also clean the throttle body with the same stuff.

[Guest keltik]

Mine revs up to about 800rpm when the rad fans or a/c kicks on. Normally idles around 550rpm hot. Idle controller is easy enough to shoot some cleaner through.

What i dont understand tho is the stalling. Im assuming your car is auto, if its stalling after accelerating - thats a TCU problem as the torque converter should stay locked up. Can you explain the stalling any better?

Also when you clean the idle control valve - pop the air assist hoses off and make sure theyre clear. The air assist hoses are the ones that run from the front of each head, next to the front cylinder intake runners, up to the idle control valve.

[Guest]

 keltik said:

What i dont understand tho is the stalling. Im assuming your car is auto, if its stalling after accelerating - thats a TCU problem as the torque converter should stay locked up. Can you explain the stalling any better?

It wont be a torque convertor assosiated problem, also the torque convertor should not stay locked up. It usually locks up after all other parameters are met and speed is above 60kmh on the gt30's.

[RSB]

Check your TPS.

[Guest]

Will try the Throttle Body cleaning trick. Its booked into Sublab tommorrow now so will mention this and get them to do it. In regards to the stalling , the car is idleing at under 500 rpm at times ( on the cusp of stalling) so when a gear change is done ,Drive to Reverse as an example, this causes it to stall. When the engine fan or A/C is turned on the revs shoot to 1000-1100 rpm. Thanks for the helpfull replies