Intermittent 3rd gear start and no first downshift
#1
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From: Northwest AR
Intermittent 3rd gear start and no first downshift
So this was rarely an issue with the stock 98 trans in my car, it was rebuilt and still did it occasionally. Then a dyno mishap destroyed the built trans and it was built again and I changed the solenoids.
Now it's occassionally still doing this...it happens after slow acceleration up hills it seems at a speed of 35 mph or less for a minute or two.
It will not start in first gear from a stop, it will not downshift to first under throttle, and will not let me manually command first. Turning off the car for about a minute seems to put everything back to normal.
Any ideas what could be the cause?
Now it's occassionally still doing this...it happens after slow acceleration up hills it seems at a speed of 35 mph or less for a minute or two.
It will not start in first gear from a stop, it will not downshift to first under throttle, and will not let me manually command first. Turning off the car for about a minute seems to put everything back to normal.
Any ideas what could be the cause?
#2
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From: Joliet, IL / Virginia Beach, VA
By your sig, I assume you have an LS swap Chevelle with a higher than stock stall converter. Nice. Check your codes. I bet you have a p0751 and/or p0757. Do a search on them if you would like. I had the same issue with the P0751, I just tuned both those codes out and never had the issue again. With mine, I think I had only 2nd and 3rd gear, no OD and no T/C lock-up. Good luck.
#3
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From: Northwest AR
code for p0757 solenoid b stuck on
Replaced these with used ones during the last rebuild...gonna drop the pan for fresh oil and filter since it's broken in now I'll put a new one in while the pans off and see if that fixes it....only occurs after going up steep hills for some reason...trans isn't hot either.
Replaced these with used ones during the last rebuild...gonna drop the pan for fresh oil and filter since it's broken in now I'll put a new one in while the pans off and see if that fixes it....only occurs after going up steep hills for some reason...trans isn't hot either.
#4
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From: Joliet, IL / Virginia Beach, VA
Whats happening is that when you shift, the RPM's aren't dropping far enough and the PCM thinks the trans is not shifting into the next gear when if fact it is. The PCM thinks the solenoid isn't switching and throws one of the two codes I mentioned earlier. 9 times out of 10 your solenoids that are in the car are fine. So instead of replacing good solenoids, you can just thank me, have the codes tuned out, and send me a check for the amount you would have spent on the solenoids.
#5
You need to turn the code off in tuning its a common issue with high stalls changing the solenoid will not help since there nothing actually wrong
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#7
So did this work?? I just installed a Yank SS4000 and got going down the road and it got stuck in 3rd. CEL came one and it was this same code. Tranny is fresh rebuild. It unstuck itself and is fine now but still got the code.
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