"Steve Barker" wrote in message ...
On 6/2/2012 4:48 PM, 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?

i missed the original post, but i'd be looking for a vacuum leak.
Probably on a gas deteriorated pcv line.

--
Steve Barker
remove the "not" from my address to email

Thanks Steve. Will check this out.