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zedbear

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zedbear Enthusiast

zedbear

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The other day I came to a stop light and sat there for about 30 seconds. Truck was not warmed up all the way at this point. When I started to drive away, it felt like it was stuck in 2nd or a higher gear. I let off the gas a little bit and then it fell into first and I drove away normally. Just wondering if this is a common symptom for something. Trans fluid is full and unburnt. Thanks.

rodram Enthusiast

rodram

Posted
Posted

... you may have an intermittent electrical or PCM issue that throws the transmission into limp-home mode... take it to a transmission mechanic shop and get it scanned for trouble codes....

 

 

What is "limp-home mode" ? This is a fault mode in which the transmission either loses electrical power or the PCM deactivates all of the electronics. The transmission will default to max line pressure. The driver will have Reverse and 3rd, with manual 2nd available by putting the gearshift in 2 or 1 (doesn't matter). 1st, 4th, and TCC lockup will not be available. It will not hurt the car to drive it like this for short periods, but use manual 2nd to get the car moving, and be aware that the trans will generate more heat than normal while operating in limp-home mode due to increased torque converter slippage during 2nd gear starts and no lockup in 3rd gear.

zedbear Enthusiast

zedbear

Posted
  • Author
Posted
... you may have an intermittent electrical or PCM issue that throws the transmission into limp-home mode... take it to a transmission mechanic shop and get it scanned for trouble codes....

 

 

What is "limp-home mode" ? This is a fault mode in which the transmission either loses electrical power or the PCM deactivates all of the electronics. The transmission will default to max line pressure. The driver will have Reverse and 3rd, with manual 2nd available by putting the gearshift in 2 or 1 (doesn't matter). 1st, 4th, and TCC lockup will not be available. It will not hurt the car to drive it like this for short periods, but use manual 2nd to get the car moving, and be aware that the trans will generate more heat than normal while operating in limp-home mode due to increased torque converter slippage during 2nd gear starts and no lockup in 3rd gear.

 

It only does this for a couple seconds. Actually hasn't done it for a week or so. I may just change the fluid and filter at this point. If it starts doing it all the time, I'll take it in. Thanks.

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