Good evening,

Yesterday, the car started acting funky and sure enough after checking the diagnostic code reader, I got a 121. So I changed out the 016 AMM and now all is well again. The fact is, this has been going on for the last year, where about every 2 months or so, the car starts stalling or gas mileage drops dramatically, I check the code reader and sure enough 121, so I replace the AMM.

As I recall, I've now used four AMM's. Now all have been used, which I picked up on ebay, so the hit hasn't been too bad. You might say ah-hah, your thermostat is stuck and allowing preheated air to torch your AMM. However, I've attempted to keep the car stone stock, so I've left things the way they are (including the heat shields) but I have replaced the thermostat and have checked it's operation to ensure the flapper works correctly.

I'm thinking that maybe the burn off function may be the problem. I see there is a procedure in Bentley's for checking burnoff but it doesn't say what voltage spike I should be observing four seconds after the car is shut down. Nor does it say where the main relay is or how to check it. So I'm looking for some help as to how to proceed with diagnosing the problem....if a problem does in fact exist.

I suppose that with the used AMM's, maybe I've been especially unlucky with units that had very limited life, but I would think that 2-3 months for all four is a detail that is telling me something.
I guess I could wire the flapper as so many posts have suggested, but I don't think that's the problem.

Lastly, can I bench test the ones that are 121 dead. Maybe a soaking in carb cleaner could clean them up. I'd like to diagnose exactly why they are dead too. Can they be visually inspected?

Can you offer some help. Thanks a lot,

Marty Wolfson
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93 244 175K, 93 244 109K, 93 245 115K, 99 V-70 84K