I have a 2001 Bonneville and the transmission shifts hard from 2nd to 3rd and 3rd to overdrive. It is not smooth at all almost jerky into each gear. I have heard the Pressure Control Solenoid (PCS) would cause this. Does anyone have an idea what it could be?

Also the gas gauge on the car is always full. No matter how much fuel it has in it, the gauge stays on full. Would this be the sending units fault? Any info on either of these problems would be very helpful.

Thanks

It probably is the PCS. Very high failure rate. Should be monitored with a scan tool to make sure...



Sounds like wire short to ground from sender to gauge. Maybe...

when is the last time that you changed the transmission fluid ? that might be your only problem

when is the last time that you changed the transmission fluid ? that might be your only problem


Not since I have had it, but the transmission fluid looks like it is brand new.

how long have you had the car for
trust me a transmission flush works a long way my car would not even go out of 1 st gear I changed the fluid added some lucas and the transmission is like brand new

On this paticular tranny, the 4T65E. Oil pressure, shift timing and shift feel. Are all controlled with solenoids. The tranny is "completly" computer controlled. Either the computer is "commanding" high oil pressure. Or the PCS has failed. It should be diagnosed. I bet a person could hook up a pressure gauge and computer scanner and know for sure whats up in an hour. Thats about the same price as a tranny service. But, you could go either way. Tranny service/flush, then diagnose, then fix problem. Or, diagnose, fix problem, then service if you want. Most model vehicles with this tranny, you have to remove tranny to get side cover off.

And while the techs are replacing the PCS, have them retorque the channel plate too. Or best yet, just install the new version gaskets. If, you plan on keeping the car.

$1000 fix beats $3000 rebuild.

This is all as long as its diagnosed correctly.

Thats the way tranny guys do it.

Same problem here on my 98' Bonneville. It is at the dealer now and they told me it was the Valve Body Solenoid and the plate assembly that needed to be replaced for a guarantee fix. Cost $939. Estimates on rebuilding $1800 to $2200. My be slightly different on the 2000 and up Bonnies.
G.W.

12 mts. ago I had the same issues with the slamming when shifting. I also hear a wining sound from the tranny. I pulled the code and they told me that I had low pressure. When I restarted the car it ran fine. However, after changing the fluid, I drove for 13 mts without trouble . Now, its back and changing did not work this time. However, it does not happen all the time. AAMCO told me $2800 to rebuild. I looked locally and the prices dropped to $1100. I suggest to get away from the dealer and the big name companies.