P0741 TCC torque convertor stuck off

[shakelton]

Hello again,

After only about 250 miles since I replaced my steering rack and wheel bearing hubs I have this (I assume completely unrelated) service engine soon issue. I checked with my OBDII scanner (I couldn't get the onboard method to work) and got this code: "P0741 torque converter CKT performance or stuck off" From reading other threads I understand that most likely the TCC solenoid has failed which means the torque convertor will not lock up at 41 mph, if I drive it this way, I will have slightly worse fuel economy and possibly overheat my transmission. The repair requires removing the transmisson from the engine and will cost about $1,200.00 to $1,500.00. Is my summary true? does anyone have any more info about this? 1998 DeVille with 144,000 miles Thanks

[BodybyFisher]

There is a TCC solenoid in the side pan. This problem can be caused by that solenoid or a problem with the torque converter. The first thing I would do is to clean the main transmission connector with electrical contact cleaner. Coolant and tranny fluid can get into that connector and cause problems. Lets eliminate that first, because its easy enough.

Last year I tilted my engine/tranny carriage removed the side over and replaced the ISS sensor, TCC solenoid and the Pressure solenoid. It was a big job but I did a LOT of other work also.

You might be able to take this to a shop that has a TECH 2, that can do advanced diagnostics. Given your technical prowess, tilting the engine is well within your capabilities.

[shakelton]

There is a TCC solenoid in the side pan. This problem can be caused by that solenoid or a problem with the torque converter. The first thing I would do is to clean the main transmission connector with electrical contact cleaner. Coolant and tranny fluid can get into that connector and cause problems. Lets eliminate that first, because its easy enough.

Last year I tilted my engine/tranny carriage removed the side over and replaced the ISS sensor, TCC solenoid and the Pressure solenoid. It was a big job but I did a LOT of other work also.

You might be able to take this to a shop that has a TECH 2, that can do advanced diagnostics. Given your technical prowess, tilting the engine is well within your capabilities.

Thanks for the quick response. I will try your suggestion of cleaning the main transmission connector. Is it easy to find? I will look in my Haynes manual (need to get an FSM). Can I use Mass Airflow sensor cleaner for electrical cleaner? I have an aerosol can of that. Hope I don't need to tilt the engine and change the sensor, but I am quite confident I can do it with your help. "What one man can do, another can do" Anthony Hopkins in the move "The Edge". Thanks

[BodybyFisher]

The connector is located at the leading edge of the transmission located behind the ABS motor. Here is a photo. Yes you can do this, and we/I can help. When I get a chance, Ill post a link to my ISS job.

[BodybyFisher]

I don't know what the MAF cleaner is comprised of. I used specifically Electrical Contact Cleaners

Here is a photo

This is the connector before cleaning

This is after cleaning

Here is the connector location,

Another View under my hand to the left is the front exhaust manifold, you can see the hole for the O2 sensor, you are looking at a location that is rearward of the driver side of the radiator

[shakelton]

These are great pictures. I am not yet familiar enough with my car to recognize exactly where this is. I'll have a look tommorow in the daylight and see if I can match up your photos with my engine. Is this on the drivers side visible from under the hood? It looks very unobstructed in your pictures, obviously some parts are removed. I found some other info on the web about replacing this solenoid in GM cars, it mentioned that it was possible for a DIYer if it is a 3T40 transmission, but to leave it to the pros if it is a 4T40. I looked under my car tonight and found these numbers: Engraved in the aluminum GYU264922, second line LDS4K. On a green lettered plate: HYDRA MATIC 8BBN6. on a bar code sticker visible from under the hood: GM#24213654. Do any of these tell me which transmission I have? BTW, I erased the codes and the light is off, and I do not notice anything different at all in the performance.

[BodybyFisher]

Its on the drivers side, Ill post a better photo for you. Look down below the intake snorkle, you will see the ABS module, if you look at the leading edge of the tranny, you will see wires coming out of it facing the passenger side. You have the 4T80-E.

Here are the specs

[BodybyFisher]

Here is my ISS speed sensor thread

http://caddyinfo.ipbhost.com/index.php?showtopic=13481

Here is my thread on the Julien Date tag, you might need this to order parts

http://caddyinfo.ipbhost.com/index.php?showtopic=13285

[BodybyFisher]

Here is an exploded view under the side cover. The Pressure and TCC sensor are mounted on the upper valve body #300 that you see here

[BodybyFisher]

The TCC will lock up at 41 mph. You can test this by driving in excess of 41, keeping your foot steady on the gas, and lightly tapping the brake, the brake will cancel the TCC lock up and your RPM will increase about 200 RPM..

[shakelton]

The TCC will lock up at 41 mph. You can test this by driving in excess of 41, keeping your foot steady on the gas, and lightly tapping the brake, the brake will cancel the TCC lock up and your RPM will increase about 200 RPM..

Thanks Mike, I just read the ISS speed sensor thread, everyone calls you Mike, hope it's OK for me too. I will try this test on my way to work tomorrow. I must add my congratulations also, after reading through that highly complex repair. Maybe I will get lucky and the code will not re-appear. If it does, I will be re-reading that thread very thoroughly. Thanks again.

[BodybyFisher]

You will like this, Logan thought up this method to drop the engine carriage, screw bolts into the frame and back the nuts off to drop the carriage in a controlled method

[BodybyFisher]

Ugh, I finally found the photo I was looking for, this shows the location of the plug clearly

[BodybyFisher]

The TCC will lock up at 41 mph. You can test this by driving in excess of 41, keeping your foot steady on the gas, and lightly tapping the brake, the brake will cancel the TCC lock up and your RPM will increase about 200 RPM..

Thanks Mike, I just read the ISS speed sensor thread, everyone calls you Mike, hope it's OK for me too. I will try this test on my way to work tomorrow. I must add my congratulations also, after reading through that highly complex repair. Maybe I will get lucky and the code will not re-appear. If it does, I will be re-reading that thread very thoroughly. Thanks again.

You are welcome, Mike is fine. Good Luck, let us know how it goes, we should be able to help you get through this

[95SevilleSLS]

Mine comes and goes. I would say it's probably going to come back on.

Mike, good picture of the tranny plug. I've been looking in the wrong area this entire time. Can you get to that from the bottom or is it easier from the top?

[BodybyFisher]

Mine comes and goes. I would say it's probably going to come back on.

Mike, good picture of the tranny plug. I've been looking in the wrong area this entire time. Can you get to that from the bottom or is it easier from the top?

That is hard for me to say, because as shakelton noted I had everything out at the point I took this photo. If I had to guess, it would be easier to get from the top with the intake snorkle out and the air box out and reach down.

[shakelton]

Mine comes and goes. I would say it's probably going to come back on.

Mike, good picture of the tranny plug. I've been looking in the wrong area this entire time. Can you get to that from the bottom or is it easier from the top?

That is hard for me to say, because as shakelton noted I had everything out at the point I took this photo. If I had to guess, it would be easier to get from the top with the intake snorkle out and the air box out and reach down.

It is very easy from the top. I just disconnected mine tonight and sprayed it with cleaner. Just as Mike described, remove the air box and turn the intake snorkel 90 degrees and you will have easy access to it. There is a plastic stem attached to a sheet metal bracket, you can squeeze the stem with pliers and push it through the hole.

Also, I tried the test drive over 41 mph and tapping the brake. I did it many times to verify the results. The rpms increased between 50 and 150. I believe that means it is working. At my work we never use the word "fluke" and mechanical and electrical problems never heal themselves, so if it continues to work I will attribute it to cleaning the electrical connector, and not luck!

Thanks for the advice and pictures.

[BodybyFisher]

See this thread, it is for the ISS speed sensor that is deeper than you need to go, but this is a very good description of getting to the side pan. I believe he drops the entire carriage. We have since used the bolt method and only dropped the driver side while just loosening the pass side carriage bolts. His illustations and presentation is worth the read, I think you will appreciate it after seeing your power point slide show

http://www.caddyinfo.com/pc0717.htm

By the way, when you get ready to tilt your engine let us know, Logan and I have done it along with few others. You need to disconnect the stabilizer link on the pass side, and I broke loose the pass side ball joint. You need to disconnect the main wiring harness from the relay center. I still can't believe that I did the ISS job, I had neighbors betting that the car would never run again, I would do it again however, but this time, I would replace the main wiring harness (it leaks into the plug) and the two thrust bearings on the drive chain sprockets. I could kick myself for not replacing those bearings, they are bad.

[Logan]

Oh...I'm keeping a picture of that. Another person using the rod method. Got a nice email recently about the rod-drop method.

"Thanks so much for your help (and pics), I completed my TCC solenoid replacement about 6 weeks ago using your technique (well almost, I took out the radiator too). replaced the alternator with a Bosch (~$225) and drained as much transmission fluid as I could (bottom pan drained), about 9 quarts to refill with Dexron VI, replaced the side cover transmission filter too as well as the serpentine belt.

Runs much smoother now.

If imitation is the highest form of flattery, you should be flattered."

We are.

[95SevilleSLS]

What kind of electrical plug-in cleaner should I look for and what would it be called? I'm going to check this out on Sunday and see what I can do.

[BodybyFisher]

What kind of electrical plug-in cleaner should I look for and what would it be called? I'm going to check this out on Sunday and see what I can do.

If you go to your best local parts store, (Napa, Pep Boys, etc) you will find Electrical Contact Cleaner in a spray can, it dries very fast, spray it into each side of the connector. Key off of course. You might scrub it with an old tooth brush. Don't be afraid to spray it good, disassemble it as much as you can. Compressed air to dry it out would be good too, buy a can if you don't have a compressor. Don't be surprised if you find grit, moisture or tranny fluid in the connector.

Do not attempt to physically clean any of the pins/sockets, just spray

[lothos]

I'm going to try this soon, too, to try and cure my P076.

The electrical cleaner I have is called something like QD Electrical Cleaner, Quick Drying. It was only a couple bucks from Checker Auto.

If you have a Fleet Farm near you, it's on sale along with Brake Kleen and a couple of other products for a little over a dollar a can this week.