Saturn SL2, 2001, 134,000 miles Engine Idle Problem

2001 SATURN

DBGAUGER

MEMBER
3 POSTS

I'm having engine idle problems. When stopped, car in drive, the engine will rev to about 1500 rpm's then settle back to 800 rpm, usually. Sometimes when I stop and then put it into park it will rev to about 3000 rpm. It seems to also fluctuate while driving

I replaced the Idle Air Control valve and cleaned the EGR valve. No real improvement.

Any suggestions would be appreciated

Nov 8, 2007 at 9:24 AM

2CARPRO JACK

✓ASE Certified Mechanic
11,533 POSTS

Has the check engine light been on? Check for vacuum leaks at the engine. If the light has been on, have it scanned for codes, might give us a place to start

Nov 9, 2007 at 7:54 AM

DBGAUGER

MEMBER
3 POSTS

No check engine light. I replaced the coolant sensor. The scan is showing that the engine temp was at -40-degrees. Obviously not correct.

Are there two coolant sensors on this engine?

Nov 12, 2007 at 5:44 PM

2CARPRO JACK

✓ASE Certified Mechanic
11,533 POSTS

There is a coolant sensor (PCM) temp sender (gauge) and air intake temp sensor (PCM)

Does it still read -40 ? be sure you replaced the right one, the temp sender and coolant sensor look alot alike on Saturns

Nov 13, 2007 at 7:29 AM

DBGAUGER

MEMBER
3 POSTS

I replaced both sensors and it's still reading -40. After replacing the sensors it corrected it for a short time. Could it be the computer itself?

Nov 19, 2007 at 9:50 PM

2CARPRO JACK

✓ASE Certified Mechanic
11,533 POSTS

Could be, but first you will need to do a pin to pin resistance check on the wires to be sure they are good to the PCM

Nov 20, 2007 at 7:52 AM

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