85 TPI 383 starting malfunction
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From: Crestwood Mo
85 TPI 383 starting malfunction
While investigating a "no pass" emissions test, oxides of nitrogin, a starting problem surfaced. The engine accelerates to about 2000 then dies , much like a catastrophic vaccum leak but with a rich mixture.. It had always passed emissions however I did notice a lean mixture with my scanner before this latest disaster. I checked out the EGR and the solenoid, TPS switch, IAC, MAF sensor, relays for resistance and beat this, no trouble codes on the scanner or by grounding A and B.... Tried a different computer - no change...Anyone who can figure this one out should get a gold star... I'm baffled... One thing, could the cold start injector cause a similiar problem?????
Burning Brakes
Joined: Nov 2003
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From: Redding Ca
I think Oxides of nitrogen are primarily caused by detonation. That coupled with the erratic idle sure sound like a vaccuum leak. Also, I believe pre ignition in an engine that should pass (383's can run very clean, depending on mods) can often result from malfunctioning smog equipment. Rots of ruck in you erection Mr Nixon! 
Last edited by GeosFun; Jun 2, 2005 at 08:29 PM.
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From: Crestwood Mo
85 383 starting malfunction
Originally Posted by GeosFun
I think Oxides of nitrogen are primarily caused by detonation. That coupled with the erratic idle sure sound like a vaccuum leak. Also, I believe pre ignition in an engine that should pass (383's can run very clean, depending on mods) can often result from malfunctioning smog equipment. Rots of ruck in you erection Mr Nixon!
I agree with your assessment but to date everything seems to be functioning properly. Appreciate your time to take a look.....
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From: Crestwood Mo
85 383 starting malfunction
Originally Posted by Bluevette85
O2 sensor working?
New O2 sensor. With the key on and the engine off I am receiving a small amount of current, .34 volts coming from the ECM. The last time that happened it was due to a malfunctioning knock sensor. At that time the current from the ECM would not allow it to go into close loop. Naturally the O2 sensor creates its own current when it heats to 600 degrees. Thanks for your time and thoughts....
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From: Crestwood Mo
85 383 starting malfunction.
Originally Posted by Morley
Check the cold start injector for a vacuum leak, it will do just what you describe (start problem)
Keep that thought in mind, I'll be there next Thursday.. I have a super ram manifold and machined the cold start injector into the unit.. Thanks for the suggestion.....
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From: Crestwood Mo
Originally Posted by 62k
Keep that thought in mind, I'll be there next Thursday.. I have a super ram manifold and machined the cold start injector into the unit.. Thanks for the suggestion.....
Indeed it was, in part, due to a leakage if cold start injector. Found one other small leak which helped create the starting havoc.
Thanks, never too old to learn something new.....
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