Here is where it all starts, my 87 240 stalls out when you give it gas, idles rough and back fires with no power, so I disconnect the amm with the car turned off and re plug it in and she runs fine, this has been going on once in a while for about 6 months. Last week the same thing happened, so I did the same with the amm and no change. I went out and put a good used amm in from a honest Volvo guy with no change. So I had the car towed in to a local Volvo shop. They fixed a wire in the harness down by the Jetronic (Brain?) and the car ran great for a day. The next day I went to start it up to the same problem as before, no power, back fireing, loading up, etc., so I unplugged and plugged the amm in and she has been running fine for the past 2 days. All the tune up parts are also new.

Thanks in advance for any input you could give me on this.