Stumble issue
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Under My Car... brb
Joined: Jun 2004
Posts: 386
Stumble issue
Been searchin for days and no clear direction. This is the closest I have found to my problem.
"The car wont rev higher than 3000rpm and stumbles and backfires under that. this started happening once it started to get hot out (90+ degrees) but im not sure whats wrong. ive changed the dist cap/rotor, wires and plugs. it helped a little but that not much."
The car is an '83 N/A. It all started a couple of months ago during a rainy morning. I first adjusted the TPS and the car ran great for a few weeks. The problem started very intermittantly again. I replaced the TPS and adjusted via the FSM. Car ran greta for a few more weeks. Then it started again. I removed and cleaned the AFM and connector terminals. Ran better for a little while. I have checked all of the vacuum hoses rechecked the AFM and TPS. I drove it 80+ miles on Sturday night when it was nice and cool out, around 80 degrees and it ran like a champ. I had just disconnected the battery and put dielectric on most of my connectors to see if it would help. Three days later I went home for lunch and couldn't get it to idle or run at all. The water pump and manifold gaskets have been replaced and my timing gun won't read because of the high quality plug wires. Too much sheilding to get a read. I guess my question is what sensors contribute to the fuel mixture? Which ones combine to tel the ECU to richen or lean the A/F ratio? I have the FSM but it doesn't clarify and my brain is too flat to decipher all of the info in the engine management section. Please help!!!!
"The car wont rev higher than 3000rpm and stumbles and backfires under that. this started happening once it started to get hot out (90+ degrees) but im not sure whats wrong. ive changed the dist cap/rotor, wires and plugs. it helped a little but that not much."
The car is an '83 N/A. It all started a couple of months ago during a rainy morning. I first adjusted the TPS and the car ran great for a few weeks. The problem started very intermittantly again. I replaced the TPS and adjusted via the FSM. Car ran greta for a few more weeks. Then it started again. I removed and cleaned the AFM and connector terminals. Ran better for a little while. I have checked all of the vacuum hoses rechecked the AFM and TPS. I drove it 80+ miles on Sturday night when it was nice and cool out, around 80 degrees and it ran like a champ. I had just disconnected the battery and put dielectric on most of my connectors to see if it would help. Three days later I went home for lunch and couldn't get it to idle or run at all. The water pump and manifold gaskets have been replaced and my timing gun won't read because of the high quality plug wires. Too much sheilding to get a read. I guess my question is what sensors contribute to the fuel mixture? Which ones combine to tel the ECU to richen or lean the A/F ratio? I have the FSM but it doesn't clarify and my brain is too flat to decipher all of the info in the engine management section. Please help!!!!
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Joined: Jun 2011
Posts: 21
From: New Mexico
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