[CREWZIN]

Originally Posted by scatgo

Ill look into the IAC. As far as the PCM I thought a rough idle would set off a code for a misfire because it is running so rough.

Thanks

Yes, IF there's a misfire. Your rough idle could be caused by numerous other conditions.

From PT Cruizer.com:

All Chrysler vehicles with fuel injection have had some form of "error checking." In many older vehicles, a person could easily turn the key back and forth a few times to get a two-digit code. With the PT Cruiser, a longer code seems to be used. In addition, as with all vehicles sold in the United States, the system is OBDC3 compatible, so that a standard diagnostic device can be plugged into a standard jack to get computer codes.

When some problems are found, the computer lights up the "engine light;" others are ignored until a mechanic asks for them. The "engine light" stays on when a serious emissions or engine problem is found, until the code is erased.

Chrysler vehicles have a "limp in" mode which reverts to a pre-programmed "guessing map" for timing, fuel delivery, etc. when a critical sensor fails. Those who have been in other cars when their oxygen sensor failed can feel grateful for this feature, though it can be confusing - for example, in some (maybe all) models, the automatic transmission is limited to second gear! The engine light also turns itself on for two seconds every time the car is started so you will know the bulb still works.