[89 GTGHOST]

Ok, this is for the EEC gurus..my buddy has an 89 gt like mine with almost identical setup..all of a sudden he started getting a check engine light...with a code 66 - mass air voltage below minimum value. When the light comes on the car starts running super rich and smoking out of both pipes. He has tried a new mass air,new processor, and replaced the harness between the processor and the mass air. The car has a new eger,evp, o2 sensors,iat and idle air motor...any suggestions? Only thing that has not been replaced is the baro..but it checks ok.

 

[meangreen92]

My guess is a bad connection somewhere, possibly the salt and pepper shaker connectors next to the EGR valve.

 

[89 GTGHOST]

He thought about that so he got a mass air conversion harness that runs from the mass air to the pcm and put it on to bypass the stock mass air wiring and stil the same problem.

 

[meangreen92]

I'd try swapping in a known good BAP. You can also try the wiggle test. With the key on, and the engine off, activate test mode for ten seconds, deactivate it, and then reactivate it again. Now you can wiggle all EEC associated wiring, and if a loose connection is found, the check engine light will illuminate - or, if you use a tester, it will acknowledge the fault.

Then I guess I'd try swapping each and every sensor as a last resort, starting with the ACT and ECT. This scenario is alot less undesireable if you've got another 'Stang around. Good luck.