This was in my 2000 xj sport 4.0
To start off with this whole story, I replaced the engine at 210k because of piston failure. While I had it out, I took it down to get rebuilt - 1st thing I wished I had never done. Since then, I have had nothing but trouble with the transmission. The first torque converter was bad, the cone on it was oblong just ever so slightly making a horrendous noise, so I had to take it back to get a second one. Since the second one was in, I was getting a slip in 4th gear after the torque converter would lock. Im talking between 75 - 150 rpm, just noticeable to the untrained ear (my wife). I kept being told that this was not a slip but rather the tcc solenoid was not staying locked by the shop and the online community….But it sure felt like it was locking up, then slipping - not unlocking. Anyways, so I took it back again (2nd thing I wished I would have never done) to have it checked out. The shop replaced the converter clutch solenoid assuring me that was it. In the mean time, I spent the $50 and replaced the brake pedal switch and the TPS sensor after reading the “unlocking trans threads” so that I could definitively rule them out. With in 500 miles, the CEL came on again with the p0740. So I took it back and demanded that the torque converter be replaced since according to them, everything else was checking out and it had the new TCC solenoid. The shop said they would go thru the entire trans again but I don’t think they did because I got it back and again the CEL came on 300 miles after I got it with the torque converter still slipping. At this point, the shop had the vehicle for a total of 1 month out of 2012 and I was done with them. And on hind sight, as easy as this trans now appears I wished I would have never taken it to be rebuilt.
So I personally double checked continuity thru all the wires, and everything was coming back good - pulled the trans pan and ohm’d the solenoids all good (between 11 and 12 ohms) and also checked from the TCU after reconnecting them, still good coming back with the correct ohms. The next step was to road test it. I left my probe in the suspected TCC lock wire out of the TCU and watch it as I was driving. It was showing 13v at lock up and indeed, the torque converter was locking. I was real curious what it would show when the torque converter would slip (or unlock). After driving 20 miles, it started it’s shenanigans. When it was slipping, the TCC was still showing 13v so I stopped and shut everything off and flipped it to ohm’s and there it was. 45ohms from the TCC at operating temp.
http://www.naxja.org/forum/showthread.php?t=1093267&highlight=osue077
Whether or not the shop changed the solenoid when they said they did, I don’t think so but I will never know. The good news is, they offered to replace the solenoid for free after I explained my diagnosis but I’m doing the installation so that I know that it is done.
Here are my sources for my research - Thank you
for the invaluable help!
http://www.naxja.org/forum/showthread.php?t=987463&highlight=solenoid
http://www.naxja.org/forum/showthread.php?t=1093387&highlight=Torque+converter+lock
To start off with this whole story, I replaced the engine at 210k because of piston failure. While I had it out, I took it down to get rebuilt - 1st thing I wished I had never done. Since then, I have had nothing but trouble with the transmission. The first torque converter was bad, the cone on it was oblong just ever so slightly making a horrendous noise, so I had to take it back to get a second one. Since the second one was in, I was getting a slip in 4th gear after the torque converter would lock. Im talking between 75 - 150 rpm, just noticeable to the untrained ear (my wife). I kept being told that this was not a slip but rather the tcc solenoid was not staying locked by the shop and the online community….But it sure felt like it was locking up, then slipping - not unlocking. Anyways, so I took it back again (2nd thing I wished I would have never done) to have it checked out. The shop replaced the converter clutch solenoid assuring me that was it. In the mean time, I spent the $50 and replaced the brake pedal switch and the TPS sensor after reading the “unlocking trans threads” so that I could definitively rule them out. With in 500 miles, the CEL came on again with the p0740. So I took it back and demanded that the torque converter be replaced since according to them, everything else was checking out and it had the new TCC solenoid. The shop said they would go thru the entire trans again but I don’t think they did because I got it back and again the CEL came on 300 miles after I got it with the torque converter still slipping. At this point, the shop had the vehicle for a total of 1 month out of 2012 and I was done with them. And on hind sight, as easy as this trans now appears I wished I would have never taken it to be rebuilt.
So I personally double checked continuity thru all the wires, and everything was coming back good - pulled the trans pan and ohm’d the solenoids all good (between 11 and 12 ohms) and also checked from the TCU after reconnecting them, still good coming back with the correct ohms. The next step was to road test it. I left my probe in the suspected TCC lock wire out of the TCU and watch it as I was driving. It was showing 13v at lock up and indeed, the torque converter was locking. I was real curious what it would show when the torque converter would slip (or unlock). After driving 20 miles, it started it’s shenanigans. When it was slipping, the TCC was still showing 13v so I stopped and shut everything off and flipped it to ohm’s and there it was. 45ohms from the TCC at operating temp.
http://www.naxja.org/forum/showthread.php?t=1093267&highlight=osue077
Whether or not the shop changed the solenoid when they said they did, I don’t think so but I will never know. The good news is, they offered to replace the solenoid for free after I explained my diagnosis but I’m doing the installation so that I know that it is done.
Here are my sources for my research - Thank you
for the invaluable help!http://www.naxja.org/forum/showthread.php?t=987463&highlight=solenoid
http://www.naxja.org/forum/showthread.php?t=1093387&highlight=Torque+converter+lock
