Hey Guys, I figured a little "challenge" in the header might get this some more visibility.

Because I can go on and on about this, I'll try to keep it short with bullets. Bottom line, I just picked up my car from the shop after 3 weeks, my wallet is $750 lighter and I have the same issue I did when it went in. No, I didn't get taken...this really is a chin-scratcher as I've been involved in every step and understand what's going on.

In summary:

- A few months ago, I got a CEL with stomp code 1212 - EGO sensor #2
- I replaced both O2 sensors, same issue
- Did research, found vacuum leaks could cause this.
- Replaced all intake gaskets, front/rear cover gaskets AND the notorious PCV Cyclonic Plate. Same issue
- Decided this was bigger than me. Took it to my local indy. Good guys... I trust them.
- In troubleshooting, he finds the 02 trouble code to be an "open circuit" code.
- Checks all wiring for faults. None. All checks out well.
- Further scanning, he notices that there are no adaptation values, nor are there any Integrator (fuel trim) values coming from that left #2 bank per the scanner. However, at the same time we can see the 02 voltage readings so it's getting the signal to the DME ruling out an actual open circuit.
- Okay, the DME puked. I research and track down a place near me in FL http://www.ecudoctors.com/ & ship them the DME.
- They diagnose and find that a short in the EPROM socket took out a 2.5v voltage regulator for the unit. Tech advised this is somewhat a common failure and can cause strange problems.
- Received MY rebuilt DME. Same issue.
- Sent my DME back. Tech cannot find anything out of values, but begins talking with my mechanic and understands there is an issue. He sends a different DME (same Bosch Number 0 261 203 484) with my OEM chip.
- Vehicle runs better. Getting Integrator (fuel trim) values from both banks now, and you can hear the vehicle making adjustments. But...
- Per scanner (AutoLogic), the DME is still showing no (read: zero % on both banks and both short term/long term) Mixture Adaptation values AND the freakin' CEL is on again with the "open 02 circuit" code when, per the scanner there are good 02 voltage values.
- My mechanic is saying it's the DME. My DME tech says everything checks out and that it's likely something else on the car. But both suspect it MAY be the EPROM got corrupted.
- I contact Mark D. (Guys, he's great!) He's not heard of this issue before, but also agrees that with two separate DMEs, the only constants are the OEM EPROM and the car.

Okay, here's the challenge:
What's going on? I need to know which way to go with this? DME, EPROM, or something else on the car.
Can an EPROM get corrupted?
If so, could the symptoms listed be from the EPROM, or something else in the DME keeping in mind two separate DMEs have been used?
What else, if anything, on the car would prevent the DME from producing Mixture Adaptation values and/or this "02 Open Circuit" code?

Help!

Many Thanks,

John