Lost 1st and 4th

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thegawd

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it could be your ignition switch. carbon builds up on the contacts which creates resistance. about the only way I know to test this is to measure pin e on the big round tranny plug. it should always read the same voltage as the battery the other wires are negative feeds.

I delt with this intermittently for a very long time before actually coming to a conclusion. sometimes it wouldnt happen for months and then it would be stuck in limp mode for a few days. the only variable was the ignition switch. turn it off and back on and see a different voltage.... bad ignition switch.

Al
 
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Its 3-2 control solenoid open or short circuit its down shift. Either way I replaced the throttle position sensor just to see if it would help, then it threw another code for said sensor. So I cleaned up the old one and put it back in. Trans is shift good through all gears now
 

thegawd

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I drove around with the heat shield off for a little while so I could troubleshoot on the side of the road everytime limp mode popped up. always a different voltage far from the trucks actual voltage. I just didnt know why at the time.

I guess there should also be tranny codes, not sure what on an obd1 though. you also shouldn't have a speedo or a prndl indicator light if its actually in limp mode.

Al
 
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Thanks for all the help guys, I learned a bunch of information thats going to be useful in the future that I otherwise would not have known. This forum has taught me a lot about my favorite truck so far, can't wait to get some cash in my pocket and start a build on it
 
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