bad idle,out of ideas

bullochboy

New Member
Jul 4, 2011
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savannah ga
91 gt fox body. 302 with the following... e303 cam gt40 up&low intake,bbk 70 mm throttle body cone breather. aod trans with shift kit. so far ive replaced the computer, swapped the mass air and the tps and this has not helped so i set my base idle and adjusted the tps... still no change. Put it on solis scanner andgot 2 codes, mass air and FMEM code. im out of ideas and looking for suggestions please and thanks!
 
What are the actual code #'s?

Try spraying carb cleaner near all your vacuum hoses to check for leaks.

What's your base idle set at? A lot of e cam cars need to idle around 900.

When you swapped maf sensors, did you put another used one in? Try cleaning the meter. Also. With a cone filter in the engine bay. The clutch fan will mess with the maf.

Is your idle air control valve new? If not try pulling it off and cleaning the funk out of it.

Just some things to try.
 
See the "Surging Idle Checklist for help with all your idle/stall problems.

The quick and easy way to dump the codes is in there too, and all you need to do it is a paper clip! The first two posts contain all the updates to the fixes. At last count there were 24 possible causes and fixes for surging idle/stall problems. I continue to update it as more people post fixes or ask questions.
 
Looks like you've hit most of the usual suspects, I was going to suggest cleaning the 10-pin connectors but that is in the surging idle check list. Lots of important info is exchanged between the engine and the computer through these connectors. I cleaned mine a few months ago and I did again recently because of an idle problem. The dielectric grease was already discolored and gummy. It's a real problem area.