torque converter

[djwmtown]

I have an 03 grand am 2.2 auto. Can anyone tell me which plug on the tranny controls the torque converter for 4th gear?

[GTP Dad]

Welcome to AF!!

Unfortunately, if you are looking to unplug the TCC solenoid you are out of luck. The 03 is computer controlled and you will be unable to unplug the solenoid. If you are having issues you need to take it to a mechanic with a trans capable scanner and have it scanned to see what is actually happening.

[djwmtown]

Well something is happening and for the life of me I cant figure out what it is. When I hit hard bumps when the car is in 4th it either dowshifts to third or the the tcc is "turning off"?? I mean I will go over some pretty rough road and the rpm's jump up like its downshifting. Does any one have any ideas? Something has to be loose but what could it be?

[J-Ri]

I've got a couple questions.

Are you at a speed where it's getting close to where it would normally downshift (or unlock the TCC)?

Is the road rough enough that your foot boucnes and presses the gas enough to make it downshift?


Also, if available, drive down that road with a scan tool while watching the knock sensor in the datastream. If it's seeing the road bumps as engine knocking, it may unlock the TCC or downshift to reduce the load on the engine.

[djwmtown]

Speed is not really a factor. I mean it's anywhere about 40mph and up (shifts into 4th about 40mph). Someone told me there's a sensor or something attatched to the brake pedal under the dash that works to unlock the tcc when braking. I'm gonna check that out.

[J-Ri]

That is correct. Again, a scan tool would make it quicker, in the datastream there should be a BOO (Brake On/Off) parameter. If the value changes to on, it's probably the switch. Check a wiring diagram first, but I think that it goes off the cruise control brake switch, in which case see if cruise cancels when you hit this section of road.

The only other possibility is off the brake light switch, if so, just have someone follow behind you and see if the lights come on.

[djwmtown]

Could it be possible that it's in fact going into third? Is there anything that could possibly cause it to go into third during a decent "jolt"? I'm just trying to explore all possibilities.

[J-Ri]

It sure could be, try manually shifting into 3rd when the rpm goes up. If it stays the same, it's downshifting, if it goes higher, just the TCC is unlocking.

You could check for a leaking MAP hose, if the hose is cracked it could be leaking when it's bounciung around and the computer is seeing a higher engine load and commanding 3rd gear

[djwmtown]

I'm not sure where the MAP hose is.I will find out and check it out. Is there anything else it could be besides that?

[J-Ri]

Originally Posted by djwmtown

I'm not sure where the MAP hose is.I will find out and check it out. Is there anything else it could be besides that?

There's 3 or 4 hoses on the throttle body, those aren't it, it is actually on the plastic intake manifold with some plastic tabs around it, then the hose curves off to the right (as you see it standing in fron of the car). I'll take a pic of mine, it's right up front, 20 seconds to replace including cutting a new section of hose.

There's always something else it could be, that might be the end of what I can give you, but I will think on it.

[djwmtown]

cool thanks for the help.