I took the old '83 Wagon with 140K miles on it out of the barn yesterday for the first time in 6 months and it ran great. This morning it started right up and died after about a minute. The fuel pumps wouldn't run so I replaced the fuel pump relay and the pumps still wouldn't run intermittently so I cleaned the 25 amp fuse receptacle by the battery (very dirty) and now the pump runs while cranking but the engine still won't start. I checked for spark and it looked good. I replaced the plugs since they were a little wet and still no go. I checked the new plugs and they were a little damp so I believe the injectors are firing but am not 100% on this.

So, there is spark and the fuel pumps (both) are working. The timing belt is good, and I monitored the fuel pressure on the rail and it was good. The Fuel Pressure Regulator is not leaking. I did some resistance checks on the ECU plug for the injectors and they were good. The grounds are good for the injectors.

What more could an engine want to start and run great! I spoke to an older Volvo mechanic and he said the 503 Bosch ECUs seldom failed. Could the AMM fail and cause this problem? I disconnected the AMM and still there was not a hint of the engine firing (limp mode).

Any ideas would be appreciated.