I have been working on a puzzle. a 92 chevy conversion van. 5.7l (350) , it cranks over and starts up perfectly.
runs exactly 15 seconds and fuel shuts off - dies slowly. fuel does not come on when cranked immediately - no start - unless the key is cycled to OFF position. once OFF, then it restarts perfectly>>> for 15 seconds. (I drove it home, 7 miles, restarting while rolling.)
No diagnostic error codes given. It flashes the Normal "12 Code" 3 times and repeats.
ECM had been "reset" by pulling battery (repeatedly) Old style OBD 1
believing it is related to oil pressure switch failure. Like a murphy switch "hold to start"...... I bypassed the switch - same results. The oil pressure sending unit works properly (seperate circuit, same switch)
For same problem, Online fellas have replaced Fuel Filters, fuel pumps, distributors, and throttle bodies with same results. and no answer to the problem.
So.. with a stop watch - I start it, rev to 1500rpm, at 12 sec., I cycle key - OFF - ON quickly. (it stays running). repeat at 12 sec interval, 4 Times. Engine then stays ON and can be driven normally - no error codes as well.
Shut off - if restarted soon... it starts normal. If it sets off for a bit ----> 15 sec run time again.
Using 12 second key cycling ON OFF ON >>>> runs normal with no issues, full power. I have driven like 10 miles with it that way.
Curious if You know a GM genius, Guru, on Ninja that may have the answer in your area.
I have refrained from changing the ECM, PCM and such.... since it can run ``correctly".
Thank you for your time and consideration.
Doug Whelan
507-391-1345
runs exactly 15 seconds and fuel shuts off - dies slowly. fuel does not come on when cranked immediately - no start - unless the key is cycled to OFF position. once OFF, then it restarts perfectly>>> for 15 seconds. (I drove it home, 7 miles, restarting while rolling.)
No diagnostic error codes given. It flashes the Normal "12 Code" 3 times and repeats.
ECM had been "reset" by pulling battery (repeatedly) Old style OBD 1
believing it is related to oil pressure switch failure. Like a murphy switch "hold to start"...... I bypassed the switch - same results. The oil pressure sending unit works properly (seperate circuit, same switch)
For same problem, Online fellas have replaced Fuel Filters, fuel pumps, distributors, and throttle bodies with same results. and no answer to the problem.
So.. with a stop watch - I start it, rev to 1500rpm, at 12 sec., I cycle key - OFF - ON quickly. (it stays running). repeat at 12 sec interval, 4 Times. Engine then stays ON and can be driven normally - no error codes as well.
Shut off - if restarted soon... it starts normal. If it sets off for a bit ----> 15 sec run time again.
Using 12 second key cycling ON OFF ON >>>> runs normal with no issues, full power. I have driven like 10 miles with it that way.
Curious if You know a GM genius, Guru, on Ninja that may have the answer in your area.
I have refrained from changing the ECM, PCM and such.... since it can run ``correctly".
Thank you for your time and consideration.
Doug Whelan
507-391-1345
Aug 30, 2015 at 6:20 AM
