about 7 or 8 months ago i left my house and while driving to work i noticed that my car was shifting very hard, when i go from 1st to second it feels like someone rear ended me, it happened for a bit and 20 minutes later when i took my car to GM, i shut it off, and when i started it again it was all history and wouldnt happen again
today, i left work for a bit, and when i hit the road, same problem, very hard shifting
i had a SES light on for a week or so but the car was very normal to drive, i never had the chance to scan it, so i just came home and scanned it and the following showed up

[PCM] P0442 - Evaporative Emission (EVAP) System Small Leak Detected (SES) (Old) (History) (Current) (Immature)
[PCM] P0502 - Vehicle Speed Sensor (VSS) Circuit Low Input (Old) (Immature)
[Brake] C1226 - RF Excessive Wheel Speed Variation (History)
[Unknown] P1540 - Air Conditioning (A/C) Refrigerant Overpressure - Air Conditioning (A/C) Disabled (History) (Immature)
[Entertainment] B1004 - Keep Alive Memory (KAM) (History) (Immature)
[Entertainment] B1327 - Device Power Circuit Low (History) (Immature)
[Entertainment] U1255 - Class 2 Communication Malfunction (History) (Current) (Immature)
[Personal Comm.] B2470 - Daytime Running Lamps Fault (History) (Immature)


anything might be related? i doubt it

i shut the car off at a red light, back on right away, problem stayed
i shut the car off for 10 minutes when i got home, started it back again, shes back to normal


any ideas?

Hmm, with all those unrelated codes it makes me think there'* a problem with corrosion. Is there a chance things got really wet? Remove the plugs on the PCM and check them for any kind of build up. Clean and reconnect.

The WSS and VSS are very close to each other. Check and clean them as well. Almost seems like you drove threw a deep puddle.

[Entertainment] B1004 - Keep Alive Memory (KAM) (History) (Immature)
[Entertainment] B1327 - Device Power Circuit Low (History) (Immature)
[Entertainment] U1255 - Class 2 Communication Malfunction (History) (Current) (Immature)
[Personal Comm.] B2470 - Daytime Running Lamps Fault (History) (Immature)

ever since i replaced my HU the above doesnt clear for some reason
i guess its related to it
i tried installing the factory HU back then, it cleared IIRC

Nothing there about the tranny or TCM. Weird. Maybe the VSS is affecting the TCM?

Your HU is wored into the Data Bus... making the car RETARDED !!


My buddys Deville is having the same stupid issues.

What is the fluid level like in the trans ?? How is the outer seal on the left front ??? is it leaking ?

possible, last time didnt scan it and never had a SES light, just a matter of time and it all disappeared

any better way of wiring it? lol
and the HU been in the car for over a year or so now, i doubt its part of the problem
well, i hope not lol

last time i check the fluid was over a month or so ago, and it was perfect, as for leaks i dont notice any.
1st time this happened to me months and months 1st thing i did was check the fluid, and again, it wasnt low or overfilled
shifting was horrible throughout the entire RPM range, even shifting at 2500 or 3000RPM you can feel the kick for sure. and when you hit 6 or 7k RPM, its alot worse dh2dh2

you have no trans codes...

try a flush and filter, or at least get in there and check things out

car is still under warranty for another year and a half, i hope it happens again and we can figure it out before its over
theres no point in checking it out here, they will tell me "we can not duplicated the problem at the time being" and charge me $195.00 an hour for labour
yes its $195.00 an hour at GM in Fort Crap