Flyingpants

^ Interesting, I will check that out as well. Unfortunately life is infinitely hectic and I was unable to pull the PCM. I am going to try and get to the PCM today and I will check out those O2's by weeks end....Thanks!

Flyingpants

Well I pulled the PCM and I cant see any signs of damage. I notice that the car is going into test mode whether it be KOEO or KOER whenever I start it up after it has sat for awhile. I am getting 332 and 172 and a couple 17* codes ( I couldn't quite catch them). Do you guys think this could be a grounding problem? Or like bubba said, perhaps a sensor, although I can't wrap my head around why a sensor would cause the car to go into test mode automatically. Also does anyone think it could be a bad PCM? I can afford to put some parts in this car right now I just want to consult with the "brains" on here before I blow cash that may not be well spent.......Thanks Fellas

Bubba 95SN

Unplug one 02 at a time to determine which is at fault. Spent 15 years in Lincoln, Mercury, Ford service departments. Never seen this until 12 years after left dealer. On my car. Went to Ford H manual (emissions control manual)for 95 no symptom for this. Had, will not enter test,... defective 02. I just started unpluging sensors until foolishness stopped. Never once gave code for 02.

Bubba 95SN

If 02 found not to be a issue try check STI to ECM for possible short to ground. Check with ECM disconnected. STI to pin #48 at ECM. Circuit 209 color of wire is W/P

Flyingpants

^ To test the STI to ECM would I just hook up my multi-meter to the STI and then plug it into the harness side connector of the ECM at pin 48? Am I basically looking for continuity?

Bubba 95SN

Yup, check with ECM disconnected for continuity or check for short to ground. Check from negative battery to STI. Really do suggest you disconnect the 02 sensors and see what it does.

Flyingpants

Ok so I tested from pin 48 to STI and I got continuity. I guess it is on to the O2's! I have a cool little test sheet for the O2's http://www.veryuseful.com/mustang/te...ensorTests.gif I think I will put the pony on the rack tomorrow after work and check them out.

Flyingpants

Just wanted to update this thread with the conclusion of my problems and also give a big thanks to those that helped me figure this out, it is truly appreciated. As it turns out Bubba knows his **** very well. I replaced both O2's with new units and my problems with the car entering test mode are gone! I still don't understand how the O2's could trigger an issue like that but it happened to me so I dunno...weird. Anyways big thanks again, I hope I can pay it forward somehow on here. Now onto the other issues with the car.