85 -150 302 issues
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85 -150 302 issues
What are the signs that a computer is going bad? I pulled codes and got several, TPS, O2, Knock sensor. I get a stumble off idle and intermittent miss at idle. I replaced the TPS and O2, no change. I went thru all the sensors tests in the haynes book, they all checked out, even the 2 sensors I replaced. I can't figure it out. I also cleaned the IAC and swapped it out, swapped out the MAP too with no difference. I cleaned the carbon out of the throttle body and EGR port into the manifold. That made the idle step up, so much I had to back the throttle stop screw out a couple turns to bring it down. I've searched around and couldn't find any bad wires or vacum linesthat might cause problems. On the gas it runs great but light throttle it is rough. Could the computer be the culprit?
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From: Diboll, Tx.
Have you checked your timing? Have you checked your coil, plugs, wires, cap, rotor, TFI module? What about your fuel pressure regulator? Made sure you have clean secure grounds? The e core coils are bad about grounding out on themselves. Check between the coil body and the metal ring surrounding it, if there are whitish marks, then its grounding out and needs replacing.
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From: Virginia
Pull the codes again. If you have the same codes, look for wiring problems. Mice like to get up in there and chew wires. You also can try unplugging the computer and then plugging it back in. Sometimes the large connector connections get corroded a little bit.
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I've looked thru as much as I could get to, didn't find anu wires damaged. I pulled the cap, it pretty ugly, going to go get one today and check the plug wires, maybe that will take care of the miss. I checked the codes again, unplugged the battery for about an hour to let them clear and after running it seveal times rechecked the codes, still getting 41 and 25 (O2 and knock sensor). I'll try unpluggung the computer today and crawl up under and trace the O2 wire again, I know the knock is broken off so I'm not worried about that one.
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I replaced the cap, rotor, plugs and checked the wires which were all good, the miss seems to be gone but I still have the stumble when i begin to accelerate. I rechecked the O2 wire and the plug connection was actually bad, cut it out and spliced the wire and rechecked the codes and no more O2 code but now I have a code 44 (thermactor air system inoperative<en dash> right side). I did unplug the battery and pull the computer, checked the connection and put it all back, still getting the 44 code. I guess I've got some more searching around to see whats causing this one now.
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From: Virginia
Code 44 is one for the air pump. It would be good to fix it, but it shouldn't hurt how the engine runs too much. The book says to check the vacuum lines and other lines related to the smog pump to make sure they are hooked up and none are kinked.
Is it running good now?
Is it running good now?
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It idles fine but it has a stumble just as I accelerate. If I don't push thru it it runs rough but give it more gas and it clears up and runs strong. I was moving wires and stuff around today while tracing the O2 wire, I might have knocked somthing loose that I didn't see. I didn't get the 44 code till after I did that. I did fid part of the air pump hoses hanging across the back of the engine behind the manifold and along the pass sidedown by the exaust. I didn't see any loose or damaged lines. The air pump was gone when I got the truck a few weeks ago so i guess I need take another look back there
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From: Savannah, GA
It idles fine but it has a stumble just as I accelerate. If I don't push thru it it runs rough but give it more gas and it clears up and runs strong. I was moving wires and stuff around today while tracing the O2 wire, I might have knocked somthing loose that I didn't see. I didn't get the 44 code till after I did that. I did fid part of the air pump hoses hanging across the back of the engine behind the manifold and along the pass sidedown by the exaust. I didn't see any loose or damaged lines. The air pump was gone when I got the truck a few weeks ago so i guess I need take another look back there
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