what is happing when my step dads duramax goes into something called a limp mode? when it does this the truck runs like **** but when u turn it off then back on it runs good for one pass down the track then it goes into limp mode again. PLEASE HELP
The trans is broke. It is limping because of excessive slippage or something else. It will continue to do this everytime you put the wood to it until the tranny is rebuilt and beefed up. More than likely it is limping on the 4-5 shift. The truck is going into limp mode so that you do not get stranded on the side of the road somewhere with a total failure. If you can pull the codes you will most likely pull a PO700 which is a TCM Malfunction. Basiclly the TCM senses something is wrong and limps the transmission limiting the amount of power, and torque that you will produce until the truck is restarted.
is it limping,(kicks out in 5th gear and over revs like slipping) or is it just not reving over 2000 rpm? Big difference, if it wont rev over 2000 it is running out of fuel, put in neutral, pedal to floor, wont go over 2000 rpm. If is limping, as soon as it does it, put in neutral and back to drive, will reset. but if you get right back in it it will kick right back.what does it have? more info, more help.
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