In article ,
Tony Hwang wrote:

Guv Bob wrote:
My 1990 Mitsubishi Eclipse (DSM 1G 2L non-turbo) is starts and idles cold
fine, and runs fine warmed up. When warm and I put it in neutral (AT) the
idle oscillates between 1800 and 2200 with about 1/2 second cycle time.

MAS was the first guess -- so I put a rebuilt mass airflow sensor assy in
and same problem. Checked all the connections and vacuum - all OK.

Also took the throttle assy apart and cleaned all - helped the running but
still oscillating. Cleaned Idle air motor, checked voltages and
resistance for all sensors and also voltages coming from the computer, and
all OK.

About out of ideas -- anyone have some thoughts on how to start
troubleshooting this?

Thanks in advance.

Bob

Hi,
Checked fuel pressure, filter, pump?

Only have a couple of seconds... but try Googling:

"idle speed hunting 90 Eclipse" (sans quotes)

Good Luck!

Erik