Chris,
Urs' computer problem may be that the computer has captured a fault or
there is a previous fault that has been repaired but the memory has not
been cleared. To clear the memory, remove the ECM fuse or disconnect the
battery for approx 1 minute. the light should go out until the car is
started and the computer captures another fault. To interrogate the
computer and access the captured fault, jumper pins "A" and "B" of the
ALCS (normally located under the dash near the steering wheel). Turn the
ignition switch "ON" but DO NOT start the car. The "check eng" light
will flash "once" then "twice". This indicates "code 12" which is
telling you that you are in the "testing mode". This will flash 3 times.
After this, the light will flash any fault codes that are stored in its'
memory. Each code will flash three times in secession. When all fault
codes have been displayed, it will revert back to "code 12" again, then
repeat the cycle. This is typical of "G.M." computers. He will need the
Monte Carlo service manual to identify the fault code number and it will
recommend a course of action for correction. Remember to clear the
memory when corrective action has been completed. 
Hope this helps...could be cheaper than another computer.

Rgds,

Ron Maracle '63R1498
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