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wattsie

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!997 Deville. Having trouble with computer code P0741.

Torque converter CKT performance or stuck off.

This trouble only comes up when car is driven for long point of time or in heavy traffic, when transmission is at it hottest peak. Need more infor on this trouble. Could it be a bad sensor at the transmission ????? Or something internal .

Thank you.

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Can you confirm the torque converter is locking up before temperature comes into play? At a steady speed above 50 MPH, just touch the brake pedal without really applying any brake pressure. You should feel the converter unlock and see a slight bump in RPM. Try it several times to convince yourself you are really feeling and seeing what should be happening.

It is possible your brake pedal switches are not adjusted properly. And sediment in the fluid can cause the valve to bind.

Another possibility is an intermittent connection at the (round) transmission connector making it temperature sensitive.

Any recent repairs that required the cradle to be dropped?

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

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Can you confirm the torque converter is locking up before temperature comes into play? At a steady speed above 50 MPH, just touch the brake pedal without really applying any brake pressure. You should feel the converter unlock and see a slight bump in RPM. Try it several times to convince yourself you are really feeling and seeing what should be happening.

It is possible your brake pedal switches are not adjusted properly. And sediment in the fluid can cause the valve to bind.

Another possibility is an intermittent connection at the (round) transmission connector making it temperature sensitive.

Any recent repairs that required the cradle to be dropped?

Thanks JIm will check brakes. No recent repairs. Can you tell me more about (round0 transmission connector?

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On my '98 Seville, that connector is easily seen on top of the transaxle case directly under the forward end of the master cylinder.

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

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I had this code once, I'm not sure if it ever came back.

-Dusty-

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I think he is refering to the round electrictial connector on transmission.

Have you checked the fluid level-easy to say.

I would add.... checking the transmission cooler, could cause a high heat.

This is a issue to address sooner than later as the potential cost from heat damage.

A scanner -bi directional and transcapable, would be the go to tool , reading and selecting TCM commands, brake switch position, as well as trans fluid temp.

PS: Any problem with engine operating temp/ coolant level?

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I think he is refering to the round electrictial connector on transmission.

Have you checked the fluid level-easy to say.

I would add.... checking the transmission cooler, could cause a high heat.

This is a issue to address sooner than later as the potential cost from heat damage.

A scanner -bi directional and transcapable, would be the go to tool , reading and selecting TCM commands, brake switch position, as well as trans fluid temp.

PS: Any problem with engine operating temp/ coolant level?

THanks Kev2

Engine temp runs around 205 to 212 is this normal??? Trans oil is ok ,check it all the time. Had oil changed three months ago and filter ,complete transmission was flushed.

Can drive car three to three days code will not come up.

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205 - 212 is normal. Who did the flush? Dealer, I hope?

THANKS Larry. NO, dealer did not do flush. Had this trouble with code p0741 before flush. It only came on once in a while. Once very 4 weeks. Since I had come to florida for my holidays it come on a lot more. Could be a temperature thing?? At home in ontario canada temp this time a year is a lot colder.

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I also had the same code. After the first system code reset it took another 4 months of driving before it came on again. I reset it over a month ago and it still has not come on. My Cad is a 2000 Deville.

I am at 114,000 miles, and it needs its first transmission service, which I will get from the dealer I use. Maybe the transmissioon service will stop it from coming on again, but somehow I doubt it.

I tried the press on the break at 50mph but could not be conclusive. It looked like the rpm shot up only able 200rpm.

However, I did drive the car at 65 steady and level, then shifted the car from D to 3rd gear. Isn't that another way? If the car is in overdrive for sure, then immediatly shifting to 3rd should give an indication? I think the transmission is a 4 speed auto, 1st - 2nd - 3rd - 4th (overdrive) - is this not correct?

Tom

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....I tried the press on the break at 50mph but could not be conclusive. It looked like the rpm shot up only able 200rpm.
That is correct.

....However, I did drive the car at 65 steady and level, then shifted the car from D to 3rd gear. Isn't that another way?

No. The torque converter clutch (TCC) action is not another gear ratio that you can select with the shift lever. TCC action is designed and intended to eliminate torque converter slippage at highway speeds by hydraulically "locking" the input shaft to the output shaft (or at least as much as that is possible). Locking the torque converter is a fuel economy technique.

You can "feel" the torque converter "unlocking" on vehicles that are more under-powered than a Cadillac. When attempting to pass with such a vehicle, you would feel the converter unlock a fraction of a second before the transmission downshifts to third gear ratio. I had a four cylinder Chevy S10 that unlocked the converter with the least bit of throttle activity; designed that way.

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

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No. The torque converter clutch (TCC) action is not another gear ratio that you can select with the shift lever. TCC action is designed and intended to eliminate torque converter slippage at highway speeds by hydraulically "locking" the input shaft to the output shaft (or at least as much as that is possible). Locking the torque converter is a fuel economy technique.

The torque converter clutch locks up the converter itself, basically locking the flywheel and transaxle input shaft. Much the same as a clutch does on a manual transmission

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Thanks for the clairification.

Then about how much fuel economy in mpG would you see lost if the TCC was stuck off, as the P code says?

Hi.

Guys thanks for all the infor. But I need more help to fix this trouble with th P0741 code. Only comes on then transmisson is at it hottest peak. When I shut car off and it is restarted the next day code doesn't come on. Or engine and transmission is cooled off. Code will come on till mid day if I drive car all day in traffic or long highway driving.

Need some new ideas, so when I take the car into dealer will have a better idea what my trouble with transmission is and what it will cost me. thanks to everyone .

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Hey there,

I've had the same code pop up from time to time in my 99 deville. The GM bulitin on it states that the seals used to keep tranny fluid out of a certain area are wearing out, allowing TCC apply fluid to escape and do two things, 1 oil the clutch, 2 reduce clutch pressure. Eventually the TCC will have no apply, and your tourque converter will be active all the time (this makes more tranny heat and slight loss of highway MPG (2-5% or so)).

I had a lengthy discussion with my dealer about it (my tranny no longer under warantee) he said that he's seen cars go 50 to 100k miles with this condition.. It is possible that there would be input bearing wear on your transmission and the tourque converter should be replaced if you perform a repair (per GM bulitin). He told me that it is very difficult to convince an aftermarket warantee co to pay for a repair.

The TCC (torque converter clutch) engages in 2nd, 3rd and 4th gears above a certain mph. Only in 1st is it disabled. You might be able to get a wiring diagram and divert the TCC close signal.. but that's very risky for all but the aged & experienced, and even then only with a complete schematic.

TCC lets go if you let off on the gas, or touch the brakes. Best way I've found to test it is to get out on a highway about 55mph, apply slight acceleration (very slight) and touch the brakes while listening to engine RPM (watch the gauge too).. you should hear and feel the clutch let go as you touch the brake, and re-engage immediately after letting go of the brake. Note, you only have to push the brakes enough to fire the rear-lights.. not enough to actually brake.

You could put an aftermarket transmission intercooler on your caddy.. the little oil intercooler on the front of the car is kinda pathetic if you ask me.. I was planning (after I also move to FL) to install one that is 4x the size... available at your local advance auto parts...

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