ST202 Engine Hunting on Idle, I really need help with this please Options

[bibbler]

Hi,

I have a '94 st202 Jap Import. On idle the revs are up and down as far as 1500rpm and as low as 500rpm. I took out the K&N and installed a standard air box with new filter. It has had a full service and all new servicable parts changed but it is still doing it. There is no loss of power and there is no misfire. I suspect that there is a pipe sucking in air somewhere still unable to locate it. Had a few mechanics looked at it and all are stumped.

Am I to live with it or can this be fixed.

Any information and advice gratefully received.

Thanks

Clayton

[2bcelica]

Mine does this every now and then at start up, but gets to normal idle after warming up a little bit. If it give it a bit of gas then it'll get to normal idle quicker, but if I don't it gets to normal idle around 800-900 within minutes. Not sure if this is normal for the beams, but I don't have any problems with it.

[laff09]

Check your vacuum lines for cracks, or it sounds like the idle air control valve is all gunked up

[95CelicaST]

But the OP doesn't have a BEAMS. He has a 3rd gen 3S-GE non-VVT.

I don't think that is a common problem that you should just "live with" Have a mechanic you trust look at vac lines. Sounds like you have a leak somewhere. One of the guys in my local car club has a 5th gen with a 3rd gen 3S-GE swap and it doesn't bounce around at idle.

[bibbler]

Thanks for the advice guys. There is a mechanic just down the road that has a decent reputation. I will go ask him in the morning.

Will let you know what the problem was when i get it sorted.

Cheers

Clay

[delusionz]

This is normal, It happens when you've had the battery out for a while. It will correct itself over the next few days if you don't drive your car much.

[Rusty]

hmm that low idle is quite low, its below the specs on the engine manual check: TBPS, vaccum lines, idle line/Idle valve could even be electrical


also when you say full service? timing belt water pump filters gasket etc???

This post has been edited by Rusty: Sep 29, 2009 - 11:44 PM

[kavy]

my 3SGE was doing the same thing.changed all of its fuse,it was still there.disconnected the battery for three hours(someone told me that disconnecting it for half an hour'll reset the ECU and solve the problem) it was still there.after about 3 weeks,when i was cleaning the intake pipes(i think it was the fuel line breather that was connected to the intake pipe),i took out the whole intake and started the motor.found out that the little thing was breathing loudly.stuck my finger in there and the motor sorta choked like it did during start ups and the rev dropped to 500rpm.turned off the motor and took out the pipe to clean it and found it was clogged with dust.oh,the problem hasn't reappeared so far(hopefully its solvedalso found out that the guy who i bought the car from was using the car with it disconnected.for adding horsepower. shame.............

[kavy]

my 3SGE was doing the same thing.changed all of its fuse,it was still there.disconnected the battery for three hours(someone told me that disconnecting it for half an hour'll reset the ECU and solve the problem) it was still there.after about 3 weeks,when i was cleaning the intake pipes(i think it was the fuel line breather that was connected to the intake pipe),i took out the whole intake and started the motor.found out that the little thing was breathing loudly.stuck my finger in there and the motor sorta choked like it did during start ups and the rev dropped to 500rpm.turned off the motor and took out the pipe to clean it and found it was clogged with dust.oh,the problem hasn't reappeared so far(hopefully its solved also found out that the guy who i bought the car from was using the car with it disconnected.for adding horsepower. shame.............