[Vol]

Anyone have this problem?
I have a hit and miss problem. Under a load, like going up hill or attempting to pass the car will surge. The tach can move 100-400 RPM. If I stomp it down the problem goes away. This can happen often and then not for days. It does not matter if the car is warm or cold.
Tranny down shift problem? Valve body? Torque converter?
All the injectors checked fine. Fuel pressure is good. Plugs all are fine. Wires are original.

Any help to pinpoint this problem before the car leaves me stranded would be appreciated.

There are three sides to every story, yours, mine and the truth.

[Vol]

Anyone have this problem?
I have a hit and miss problem. Under a load, like going up hill or attempting to pass the car will surge. The tach can move 100-400 RPM. If I stomp it down the problem goes away. This can happen often and then not for days. It does not matter if the car is warm or cold.
Tranny down shift problem? Valve body? Torque converter?
All the injectors checked fine. Fuel pressure is good. Plugs all are fine. Wires are original.

Any help to pinpoint this problem before the car leaves me stranded would be appreciated.

There are three sides to every story, yours, mine and the truth.

[TIAUTOMAN]

Probably plug wires. Pull off the leads at the coil pack and look for black powerder (carbon)

[TinInjun]

Possible TCC problem.

"Suppose you were an idiot... And suppose you were a member of Congress... seems I repeated myself." --Mark Twain

[TIAUTOMAN]

TCC is a possiblilty. But Ill bet its the wires.
3.8 have a bad tendency to fry wires. Its common, and I see it all the time. The TCC could be an issue, and there should be a code set, even if the check engine light isnt on.
Also it was stated that if throttle is increased, the surge goes away. With a TCC problem it would get worse (shudder). Unless the TCC is unlocking completely.

[TIAUTOMAN]

I missed something, you say the tach moves 100 to 400rpms.

[Vol]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Travis:
I missed something, you say the tach moves 100 to 400rpms.<HR></BLOCKQUOTE>

Yes. lets say I am at highway speed 55-65 mph, tach at 2100-2200 rpm. I start to approch an incline. Tach can dance from 2200-2500 back-and-forth quickly. It does not feel as if it needs to down shift most the time. If I accelerate harder it will down shift. I have tried driving the car in the third gear instead of OD or 4th gear. Same problem.

I have drove the car in this condition for some time. But Winter here in Minnesota is not the time to be messing with this if it gets worse.

There are three sides to every story, yours, mine and the truth.

[Vol]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Travis:
TCC is a possiblilty. But Ill bet its the wires.
3.8 have a bad tendency to fry wires. Its common, and I see it all the time. The TCC could be an issue, and there should be a code set, even if the check engine light isnt on.
Also it was stated that if throttle is increased, the surge goes away. With a TCC problem it would get worse (shudder). Unless the TCC is unlocking completely.<HR></BLOCKQUOTE>

Travis little help with the TCC definition. Torque converter? is my guess.
Would I want to get a code scanner to check the codes to help reveal anything else? I will look at the wires after I reply to you.

Is there a known problem with the torque converter at all? I have an uncle who just bought a used 2000 Grand Prix and is having nearly the same problem.

Thanks for your help.

There are three sides to every story, yours, mine and the truth.

[TIAUTOMAN]

If its doing it in 3rd gear It is most definelty a missfire issue. (plug wires) It is very common
especially after 45k miles.

The 2000 you are refering that to could be a missfire issue. But the 2000 has a different trans than your 97. You have a 4T60E which is controlled by vac to regulate pressure. The '00 has a 4T65E. Which is completely electronic and has a Pressure control selnoid.

From 98 untill 02 These transmissions have a problem with launch shudder, erattic shifts, delayed engagement. and a host of other things directly related to the pressure control selnoid.

Have you pulled the wires off the coil to look for a burnt terminals?

Another tip for finding a bad wire is to use a spray bottle with water and mist the wires while its running. The mist will cause the bad wire to arc. and you will most definetly see, or hear it.

[TIAUTOMAN]

TCC Torque converter clutch, controlled by the PCM and TCC selnoid. released by the brake switch.

[bluesman]

Noy saying that your problem is the same, but this sounds a lot what my 97 bonneville done last year. I had about 66k miles on the car then and I had to have the dealer tech with me to show him exactly what was happening as they couldnt get it to repeat. Mine did this at 60-65 mph but not at any load, just steady cruising on the freeway. It turned out to be some port or bore in my trans valve body that was scored and they reconditioned it. Problem gone.

Chas.

[Vol]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by bluesman:
Noy saying that your problem is the same, but this sounds a lot what my 97 bonneville done last year. I had about 66k miles on the car then and I had to have the dealer tech with me to show him exactly what was happening as they couldnt get it to repeat. Mine did this at 60-65 mph but not at any load, just steady cruising on the freeway. It turned out to be some port or bore in my trans valve body that was scored and they reconditioned it. Problem gone.

Chas.<HR></BLOCKQUOTE>
I had mine in the dealership 8 months ago. They road tested the car and could not repeat the problem either. The dealer thought the problem was transmission related at the time, but could not pinpoint it. They gave me a rough estimate of $1500. I thought I should be sure of the problem before committing to any repair quesswork.

Did the dealer have to pull the tranny to recondition the valve body? May I ask the cost?

Thanks for your input.

There are three sides to every story, yours, mine and the truth.

[bluesman]

I called the dealer that serviced it in May of 2001. (52k miles actually) He said it was in the valvebody and that they also replaced the trans oil pump assembly too. All work was done with trans in car. Though my extended warranty covered the repair, it was in the $1200.00 neighborhood. (ouch) I mentioned some of your particular symtoms to him, and like Travis said, because yours "surges" he suspected faulty plug wires. Is it possible that a cracked plug could create the same problem?

Chas.

[Mr_GTO]

Do a tune up to it. Plugs, wires, O2 sensors, air filter, etc. Check the Supercharger oil to.

[TIAUTOMAN]

A tune up is a good idea, but skip the plugs.
They are platinum, and will go for at least 80k
minimum. REPLACE THE WIRES.....Use Delco Parts.

[Vol]

I have not been able to get back here for awhile.

Here is the latest. New wires and plugs. Still the same problem. I am thinking it might be time for a trip to the trans man.

There are three sides to every story, yours, mine and the truth.