Hi, kind of a basic question here about my 98 Legacy L (automatic) sedan with 104k miles. I noticed that it used to idle with the A/C off and e-brake released at 7k RPMS. Recently, it seems to be down to 6k RPM.

 

I know they are both within the manual's specs (6-8) but was wondering if someone could tell me how to bump it up. I just had the oil changed last week. New PCV valve? Fuel filter? Injector cleaner?

 

Thanks for any help. It runs great besides that.

 

- Ed

Hi, kind of a basic question here about my 98 Legacy L (automatic) sedan with 104k miles. I noticed that it used to idle with the A/C off and e-brake released at 7k RPMS. Recently, it seems to be down to 6k RPM.

 

I know they are both within the manual's specs (6-8) but was wondering if someone could tell me how to bump it up. I just had the oil changed last week. New PCV valve? Fuel filter? Injector cleaner?

 

Thanks for any help. It runs great besides that.

 

- Ed

Hi ED, I hope you mean 600-800 rpm not thousands (K)? That would be a nippy take off !!!!!!!?

Hi ED, I hope you mean 600-800 rpm not thousands (K)? That would be a nippy take off !!!!!!!?

 

Oops, sorry...yeah, forget the k.

*bump* any ideas?

The idle speed is controlled by the ECU, so you have little chance of altering it. If a hose is clogged and the engine won't run at the correct idle speed, the ECU should complain - ie. "Check Engine".

 

 

Coolant temperature is used by the ECU to select fast idle, which can be anywhere from 800-1500rpm. Down to 600rpm could just mean the engine is at max operating temp. You might want to replace the coolant temp sensor.

Also keep in mind that the tach in the dash probably shouldn't be trusted to determine whether or not repair is necessary.

Good point 99.