1999 xlt 4.0sohc
 

Had the torque converter replaced in my 99 XLT 3 months ago.....no problems except lately, about 2-3 times/week i have been having the problem that it will die on me just before i come to a complete stop, just like the problem that caused the converter to have to be replaced. During these times it almosts acts as if its a manual transmission. It also idles very low at certain times (around 500rpm)....just wondering if anyone has ever dealt with a problem like this before? Is this just a nuisance I will have to live with or possibly a symptom of something much bigger? Or maybe an easy fix? Thanks.

sounds like a bad TCC (torque converter clutch) solenoid....it should throw a code(scan for codes)....or perhaps there is problem where trans is not sensing output speed correctly...and sending incorrect info to engage TVV at appropriate time....

disconnect the TCC soleniod and see if it acts the same....I believe you can cut the number three wire in the wire harness going into side of tranny and it will disable the tcc lockup solenoid so you can check if symptoms go away and verify a TCC solenoid/TCC signal problem.........

check http://www.p71interceptor.com/tranny...ead/index.html for a harness plug diagram.

The torque converter clutch (TCC) solenoid is a pulse width modulated solenoid that infinitely varies the slip of the torque converter anywhere from 0% - 100%. Leaving this solenoid disconnected would result in 100% slip and the associated poor fuel economy and elevated fluid temperatures. Additionally note that tcc lockup is hydraulically disabled in first gear regardless of the position of this solenoid. The pcm monitors engine crankshaft and transmission output shaft speeds. And if a lot of tcc lockup is commanded and the pcm senses too much slip between the two, it will set an appropriate powertrain code.

if its torque converter related.....perhaps the lockup is staying on. but it usually doesnt "halfway lockup"....it usually kills tranny completely

if the torque converter was trying to lock up and bringing rpms down to around 500...then this sounds like torque converter is trying to lock up and slipping....this would usually have an effect on tranny fluid over time...

check the fluid...is it showing signs of wear like stinky or discolored fluid then TCC is slipping....normal fluid should be bright red like strawberry syrup and have a faint petroleum smell...

was there any other info about other torque converter that was replaced? when you replaced torque converter did it fix problem temporarily?

to check for proper torque converter operation......get vehicle up to freeway speed in O/D and hold speed contant....you will notice rpms will drop slightly when TCC engages(around 300 rpms...give or take 50).....and when you press on the gas a little it will disengage and raise the rpms back up to previous level...

good luck....

Thanks for your response....

The problem didn't reoccur until about 3 weeks ago, and since then it has been happening frequently. So from october(the time the new converter was installed) to january everything was fine, although it still idled low. It gets to lockup and disengages just fine, and the fluid looks good.

sounds like a sticking converter regulator valve in the valve bdoy. they are bad about it. needs a valve body. those are high dollar