Greg's '88

Now that the A/C in my '88 is working so much better, thanks to the cleaned out evaporator, a new quirk has developed. This problem may have been present for a long time and we just didn't notice because we didn't use the A/C very much.

If the warm engine is started with the A/C set to "Auto" (Electronic Climate Control), the Check Engine Light comes on about 5 to 10 seconds after starting the engine. If I turn the A/C off and then restart the engine, no Check Engine Light. This is very repeatable.

It seems like the A/C compressor is engaged during engine cranking and it prevents the engine from quickly reaching idle speed. Also, the engine is a little harder to start with the A/C set to "Auto".

Has anyone else had this experience? Any suggestions - besides "turn off the A/C before starting the engine"? 8~)

Thanks in advance for your feedback.

Greg S. / Canyon Lake, CA.


[Modified by Greg's '88, 4:04 PM 6/16/2003]

SunCr

Dash assembly sends a 7 volt signal (electronic air - 12 volt if manual) to the ECM when a/c, bi-level or defrost is requested. ECM then increases IAC counts raising idle to match compressor load. Neither the IAC or the a/c circuit is on the driver circuit that controls the Check Engine Light, so assuming there are no trouble codes, sounds like an ECM fault.

JCAIRE2

Try pulling the codes and see what you get? Not sure how to start troubleshooting this one :confused:

Greg's '88

This weekend I will pull the codes to see if any are stored. I will post the results here for anyone else having a similar problem.

Thanks for the feedback.

Greg S. / Canyon Lake, CA.