Perseus
Junior Member
Need some input here.
Installed a new long block, replaced all sensors and pcm, all new ignition system from the distributor to the plugs and everything in between, had the injectors bench tested and flushed, watched the process, all checked out, reinstalled after thorough cleaning with fresh o rings, installed new o2 sensors fore and aft of a 2 yr old cat.
Probem:
engine was running adequately with not great mileage , averaging slightly less than 9 mpg, finaly replaced the crankshaft position sensor just to be safe, now the engine misfires and even stalled out on the freeway. Engine would turn over but not fire, while calling for a tow truck, I plugged in my analyzer just to try and figure out what was going on tryed it again and it started right up . No codes.
That's when I decided to swap out the pcm.
Had it flashed from the old pcm. No appreciable change.
Pulled off the tps plug and started it up just to see if it would throw a code which it did. Plugged the tps back in, code disappeared.
It would appear that the pcm is communicating, but seems to be using the analyzer as a bypass just to start the engine. Sometimes it continues to run when unplugged and sometimes it doesn't.
Any suggestions ?
Installed a new long block, replaced all sensors and pcm, all new ignition system from the distributor to the plugs and everything in between, had the injectors bench tested and flushed, watched the process, all checked out, reinstalled after thorough cleaning with fresh o rings, installed new o2 sensors fore and aft of a 2 yr old cat.
Probem:
engine was running adequately with not great mileage , averaging slightly less than 9 mpg, finaly replaced the crankshaft position sensor just to be safe, now the engine misfires and even stalled out on the freeway. Engine would turn over but not fire, while calling for a tow truck, I plugged in my analyzer just to try and figure out what was going on tryed it again and it started right up . No codes.
That's when I decided to swap out the pcm.
Had it flashed from the old pcm. No appreciable change.
Pulled off the tps plug and started it up just to see if it would throw a code which it did. Plugged the tps back in, code disappeared.
It would appear that the pcm is communicating, but seems to be using the analyzer as a bypass just to start the engine. Sometimes it continues to run when unplugged and sometimes it doesn't.
Any suggestions ?
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