Bob,
There is a TSB covering your problem. Code 1811. The fix is a new Control Pressure Valve, new oil pump shaft and re-program. These are updated parts. I have had the same problem.
I have a 2000 LS 2 v6 with traction control. The service engine light will
> come on and the car seems to shift a little harder than normal. If you shut
> the car off the light goes off for a dya or two then will do the same thing.
> I have tried to have the codes read at two different shops and they both
> could not get any trouble codes from the computer, in fact the info they
> were getting was way off. (the computer showed the enginge reving at 15000
> rpm when it was at idle, and other false data)
> Is there a seperate transmission control unit that could be out of whack?
> Am I stuck bending over at the dealer cuz this car is out of warranty?
> thanks in advance
> bob
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