Hi,

I have a 1994 940 non-turbo with a Bosch ignition system, that has been out of commission for at least 3 months and the code 121 keeps appearing even after swapping the AMM out with two different used ones.

From reading other posts on brick board, it appears that some Volvos can run with the AMM unplugged, but mine won’t even idle. After reading a post saying to check the connector at the AMM for corrosion or bad terminals, I decided to investigate the possibility. No corrosion was visible and the terminals looked fine, so figured that the wires would have to be traced back to the computer. While trying to figure out how the wires made their way back to computer I noticed some wires behind the strut tower and they had slices in them and two of the wires were attached to nothing. After tracing the wires, they indeed did go to the AMM. Upon repairing the wires the car started up immediately and returned to its smooth running condition. For about two years this car has been unreliable, particularly under any type of precipitation. I am wondering has this been the problem I have been chasing. I have replaced the CPS at least 3 times, oxygen sensor once and the wires and cap also. Do any of you 940 owners with a Bosch ignition system know if your car can run with the AMM unplugged or is this just a quirk in my car?

Thanks

Gus