2005 Impala base 3.4 79K

Recent development: sporadic transmission buck when slowing down or coming to a stop, then up-speed. Seems to only occur after driving about 150-200 miles after using the 'secret' reset method ( turning key to on, gas pedal to the floor, wait, redo, wait etc - then take car for 20 minute drive). I don't know if this 'reset' actually works of that it might be just as easy to disconnect the battery for 30 minutes and then take the car for a drive - but the bucking does go away for at least another 200 miles.

My scanner, inexpensive, although works on other cars will not read the impala.

What damage, if any, does this bucking do to the transmission? I've read a lot of answers but they all seem to be 'best guess' solutions, nothing definitive.

Replies?

 

hard to say from the description. possible torque convertor shudder? Is the check engine light on or flashing? make sure the cig fuse is good as it powers the dlc connector the scan tool plugs into. if the fuse is blown the scan tool will not power up.

 

Thanks for your reply:

The CEL is not on or flashing. The Cig LT fuse is good and the scanner does light up - and I've just now discovered that it will not read my 08 Taurus. It has read both cars in the past so I'm thinking there may be a problem with the scanner.

But that's beside the point: I'm trying to find out if the buck is doing harm to the transmission - apparently this is a common problem in Impala 2000's.

 

a ttc shudder isn't good. you need to confirm that is the problem. google torque converter shudder for an impala and see if the symptoms match yours

 

There is not a shudder.

Recent development: sporadic transmission buck when slowing down or coming to a stop, then up-speed. Seems to only occur after driving about 150-200 miles after using the 'secret' reset method ( turning key to on, gas pedal to the floor, wait, redo, wait etc - then take car for 20 minute drive). I don't know if this 'reset' actually works of that it might be just as easy to disconnect the battery for 30 minutes and then take the car for a drive - but the bucking does go away for at least another 200 miles.

 

have a good transmission tech go for a test drive. Without being there when it occurs; its pretty hard to determine the problem based on the description.

secret reset method....never heard of it. the only way adaptive learning is reset is with a scan tool.

 

You can get a cheap reader on Amazon for about $12. Then download Torquelite app on your phone (two versions, one free, one $5). Works on every GM car I have. You can even clear the maddening EVAP codes that GM can't seem to fix.

 

There is an issue with the modulator on these Trannys. My Monte Carlo does it. My Impala did it when I owned it. It was so infrequent I just lived with it. You will be sitting a a stop lite and go to take off and the car doesn't move for a sec then all of a sudden it lurches. You can go for a week or two and it won't happen again. Just another GM engineering problem they won't fix.

 

modulator? On a electronic trans? Please explain.

 

Actually the solenoid.