I have a 2002 Deville Base model. Last year the I got a TCC code that was causing an unstable idle and also stalling the car. I replaced that solenoid and the problem went away except the same code would show up off the engine light. Now the car was acting similar to last year. I just got done replacing the two shift solenoids in the valve body. ( If anyone has to do this make sure you have the correct solenoids, I found out that GM did a change to this area because of the valve body filter that would pop out and damage the solenoids). NOW the problem,,, The car starts off good but going from 2nd to 3rd it shifts a little hard. Also at cruse of 45 mph when I floor it , it will not downshift. Slowing down normally it will down shift fine. Taking off fast it seems to want to go higher in RPMs before shifting. I have a new code now for TPS(throttle position sensor) and MAP but the transmission codes are no longer there. All this being said,,,, Is it possible I did something wrong with the new solenoids,, Or could the TPS affect the downshift to pass and also create the harder shifting.

 

Yes. The TPS can cause all kinds of shifting issues, including no passing gear. The code being stored can cause the harsh shifts, as it puts the trans side of the PCM into a "failsafe" mode, which will raise the operating(line) pressure of the trans.
If you are NOT gettting ANY trans related codes, taking care of the TPS code should take care of the shifting problems.

 

Well I took the old TPS off and cleaned it, put it back on and the shifting was good ( FOR HALF A DAY ),, So I have installed a new one and now the car shifts normally and will downshift to pass,,,, however,,, if taking off at a high rate of speed you have to let off the pedal before it will shift,,, No check light as of now and the INNOVA is not picking anything up in drive mode,,, I know it has to be something stupid,,, I would think that if had done something wrong while replacing the shift solenoids that it wouldn't drive as well as it does now that I replaced the TPS,,,,,, Any thoughts

 

If you put your foot in it, it WILL shift much later.....that's how it's supposed to work. It should shift before it hits the RPM cut-off, tho.

 

After driving it a couple days now it will shift well when its cold. But when it hits normal operating temp the shifting becomes a problem. It will not shift to third gear without getting up to 45mph and then lightly letting off the gas and when it does go into third its pretty hard. Could it be possible that the idle is off? I noticed that when I replaced the TPS I had to turn the sensor a little to line up the mounting holes. By turning the sensor could it be sending the wrong position signals which is not being relayed in line with the tranny?... still no check light and INNOVA not picking anything up.

 

I tried to adjust the idle and it got a little worst. Also the light came on and the fault is P0741 saying failure in torque converter or burnt or low fluid,,, the second one said TCC stuck off . Last year I replaced that solenoid, maybe it has gone bad again, and if so could there be something else that would cause that solenoid to go bad so quickly?,,,, after changing the two shift solenoids two week ago I did check the fluid for a couple of days to make sure the level is good and its maintained well. If I do replace it again at least I know of another way other than dropping or pulling the motor out,,, takes about 4 hrs to complete but better than paying $2000.00 at a shop or dealer.

 

Whats your thoughts of it being the speed sensor? Or would that give me a different code?

 

The repeated TCC codes are not going to be corrected by replacing the TCC solenoid. The problem is NOT the solenoid...the problem is leaking seals for the TCC apply to the torque converter. The ONLY way to correct this issue is to remove the trans, replace the seals & torque converter.
Your shifting problems are a separate issue, BUT...if the PCM sets a code, the shifts will be firm.
Yes...a speed sensor CAN cause a late shift, but not normally only one shift....it would normally be all of the shifts.
Hate to say it, but it really sounds like you're going to have to have the transmission repaired/rebuilt.

 

I too have a 2002 Cadillac Deville with the TCC codes, occasionally shifting at higher points, higher RPMs at cruising speed, lower MPGs, etc. Unfortunately, that repair is a HUGE cost, so I am waiting until I can afford it. I have an "extended service contract", but it does not cover the TCC (just mechanical parts inside the transmission case).

In order to get them to cover it (a TCC is under $50), what would be the best thing(s) to tell them that need to be replaced/fixed? I don't want the shop to say it is ONLY the TCC, meaning BIG money (11 hours @ $75+ per hour). If it can be proven that something inside the transmission is bad, they would cover the repair.

TS

 

If you have codes set, and the trans is not functioning properly, the extended warranty will cover the repair. A trans shop will remove, and inspect the trans, then deal with the warranty company. They will send an inspector to the shop, take pics, and they will want a definitive "cause of failure". The cause of failure in this case is the seals in the trans channel plate that seal the TCC oil. The torque converter will also need to be replaced, due to the slippage created by the leaking seals. The TCC solenoid, in 9 out of 10 trannys with this code will be melted, or show some signs of failure.
Be aware, almost ALL Extended warranty provider will insist on copies of your maintenance records, including oil changes, etc. with mileage. If you do not have records, they can, and normally WILL decline the repairs. Just like any other "insurance", they will find any way possible to decline. A good trans shop will know how to work with them, and get the repairs authorized. You may be on the hook for some of the bill, depending on what type of service plan you have. Some warranty companies do not even pay for the trans fluid. Check you paperwork carefully, have a trans shop check the car out, and see if they can/will work with the warranty company.