1991 Buick Park Ave Control Module Failure

[Rich Hall]

I hope you can help me. I have a 1991, Buick Park Ave that runs like a dream when the control module is working. This car seems to "go through them" once every eight months. This control module was traded at on 4-16-2003, 1-22-2004, and 11-12-2004. This module is under the dashboard on the passenger side. When I replace it, the PROM is transferred from the old module to the rebuilt one.

The symptoms of the breakdown are gradual.:
(1) A red light [to the right and above the temperature gauge] blinks on for a second now and then. I have replaced the temperature sensor on the top of the engine.

(2) The red light and the "check engine" light blink simultaneously as the motor momentarily stalls for an instant.

(3) The "check engine" and the "check oil" lights come on while the speedometer gauge quits. The transmission seems to barely engage when we start from a stop, but it still runs. When the car is turned off and restarted, everything usually returns to normal.

Eventually, all this happens and the gauges (speed and rpm) don't work either. But the car continues to run. After more time, all this will happen and the engine will cut off as well.

This part is identified as a STA EM1470.

[deadring]

hi,

i'd try another ECM without swapping your prom in it.. find one that will work without touching the prom....

or it might be a short somewhere but that wouldnt take 8 months to break into a ecm failure...


deadring

[Rich Hall]

Thanks deadring:
It's the time it takes to breakdown and the consistent manner of symptoms that a interest me. I'm corresponding with the company who rebuilds them to see if the same components are overheated or something each time, but I suspect from their initial response that they clean-up used modules from collisions and send them out as replacements. That works and I appreciate the service, but they wouldn't know why the module was failing.
rich