Engine/Transmission (1998.5 - 2002) what's the real proven fix $ cause of the eratic torque convertor lock-up?????

[SGreenwood]

What's the real story on eratic (TC) lock up??

1998. 5 24v auto 4x4

I have been dealing with this problem for a couple of months and its starting to get old quick! The transmission comes in and out of lock-up very eraticly with no regular pattern except it seems worse first thing in the morning when it is moist out . it seems to get a little better after i go down the road a few miles and stay above 55 mph.

I have read all the threads on the tdr and researched the after market gadgets and i don't want to throw money down the drain.

I replaced apps sensor and still no fix . there went $300. 00 down the drain now i'm looking at replacing the alternator but i'm going to try and borrow one from a friend to see if thats it .



I would like to know what anyone else "WHO HAS ACTUALLY HAD THIS PROBLEM AND FIXED IT " has found to be the cause and what they did to fix it once and for all!

 

[thejeepdude]

Call DTT and ask them about their noise filter... if you've checked everything else, that might help... they'd be able to tell you for sure, even if that wasn't the fix they'd probably be able to tell ya what is. They've helped me with transmission issues and I haven't paid them a dime yet... although they're about to get a fat stack of dimes next week!

 

[Bob4x4]

The first thing to do would be to get the pcm flashed. In my experience it will fix 95% of trucks with this issue. Then if it still has the issue,the fun begins



Bob

 

[TurboDog]

ECM reflash fixed mine, if it comes back I will buy one of the Happibox's at happibox.com website.

 

[SGreenwood]

i have had the reflash done also last month it was ok for a couple of weeks but not sure if was the reflash that had anything to do with that ????????? does any one have the number for DTT??



more help PLEASE... ... ...



has any one found that the alternator created static or noise that interfeared wiht the apps ????

And by replacing it solved the problem????

 

[Tom W]

The DTT noise filter fixed mine.

 

[ACoyle]

I have had the problem come and go a few times. Here is my no$$ fix.



1) Disconnect all cables to both batteries.

2) Have coffee, take a nap, whatever leave them off an hour or so.

3) Thoroughly clean the battery connectors.

4) Reconnect the batteries. The time you left the cables off cleared the transient codes, if any.

5) Trun the key on and slowly depress and slowly release the accelerator. This recalibrates tehe APPS.

6) Now you have clean connections, maybe cleared some codes and recalibrates the apps.

This usually restoers happy driving.

AC

 

[mberry]

Originally posted by ACoyle

I have had the problem come and go a few times. Here is my no$$ fix.



1) Disconnect all cables to both batteries.

2) Have coffee, take a nap, whatever leave them off an hour or so.

3) Thoroughly clean the battery connectors.

4) Reconnect the batteries. The time you left the cables off cleared the transient codes, if any.

5) Trun the key on and slowly depress and slowly release the accelerator. This recalibrates tehe APPS.

6) Now you have clean connections, maybe cleared some codes and recalibrates the apps.

This usually restoers happy driving.

AC

Don't forget to check/clean the grounds.

 

[SGreenwood]

i have tried the disconnect the battery thing no difference



i have tested all the grounds on the total system.



i have cleaned the battery termnals and no difference



i did go to the link for the DTT noise filter. there info seems to make a lot of sence i emailed them to get a price and more info. they mention that the noise coming from the alternator could be the problem , and the more load put on the alternator causes more noise IE. it's more noticeable in the morning when i first start my truck becouse alternator is working harder to make up for the power that it just used to start the truck

aahhhhh bingo!



has anyone out there used the DTT noise filter ???



and what is your results ???

 

[Bob4x4]

I have installed some and they do work when noise is an issue. There are quite a few things that can produce this condition



Bob

 

[SGreenwood]

DTT did email me back with their tech phone # 1-866-504-4002



The cost of the unit is $37. 00 It's cheap enough that it is worth taking a shot at it to see if it works. I will be calling them tomorrow to discuss my truck problems with them to see if this will help. I will let you all know what they say... .

 

[JR2]

I know there is a member on here that makes a harness to move the TPS wiring away from the alternator. I have seen him selling the harnesses on Ebay a few times. I used to have a PM from him, but I guess I deleted it a while back. If you search for APPS harness it should come up. I think it was about $40 and that would be worth a try.





****Edit*****



Here is a link to the rewire kit on Ebay.

 

[c.e. linker]

look on passenger side between battery and airbox. you will find a ground wire there with a grey connector in it. take the connector apart and clean it out then put together and take apart a few times. this worked for me. bad connection there.

 

[Huff N Puff]

An erratic trans operation is not always going to be an APPS sensor

Its more likely going to be a govenor pressure transducer,its a small pressure sensor, in the trans that feeds the power train processor govenor presure infomation so the processer can make shift decisions. Watch govenor pressure on a scan tool to see if its erratic. See if it matches the actual govenor pressure on a guage. If its bouncing on the scan tool, and the converter is jumping in and out. Chances are its a bad pressure transducer. Easy to install,drop the pan,2 torxs and 3 7/16" bolts hold it in. Merv

 

[SGreenwood]

We did a full transmission check and everything checked out ok. We even hooked up a test lock up switch and a led to let us know what signal the pcm was sending the transmission. The test switch showed us that the lock was working properly when we overroad the pcm and told the transmission to lock up manualy. the led cofirmed to us that there was a eratic signal coming from the pcm. We also hook up the truck to a computer and ran a funtion test,ground test and a sensor test, the only thing that showed up was the voltage changes in the apps/tps. So of course we installed a new $300. 00+ apps/tps sensor. Which also did not fix the problem. Now we are left to hunt elsewhere which leaves us here. It looks like we will be heading in the direction of static or noise from the alternator. we do have a few more leads thanks to you guys which we will be checking out next.



Does any one know the colors of the signal wire coming out of the apps/tps sensor (remember I'm working on a 1998. 5 which has 6 wires coming from it) which controls the trans. lock-up also where does it go to (the other end of the wire) or does it change to a different color somewhere? It is my understanding that it goes to the ECM and then the ECM converts the signal and sends it to the PCM which then sends it to the trans lock-up...



thanks for whatever help you can give... ... SG

 

[richardcoxid]

Do the “re-flash”



My transmission did the same thing a year or so ago.



The transmission shop where I have my work done, with out even looking at it said that I should get the computer re-flashed. He then went ahead and used his “black box” to check out the transmission, checked “OK”



Went to the dealer and $30 dollars later went on my merry way, NO ERATIC shifting since then.

 

[Bob4x4]

You can eliminate the noise from the alternator if that is the source by disconnecting the field wires. I have also had noise from the lift pump. Test drive with what ever componet disconnected. You can not check the quality of the ground circuits easily. Save yourself some time and add a ground from the right batt directly to the pcm. Batteries themselves can also be an issue.



Bob

 

[shendren]

i have a kit that rewires the tps/apps. it's on ebay. or you can email me. i tried bills capacitor fix and it didn't work. we're selling literally hundreds of these rewire kits. this is a real problem on all trucks. not just the diesel. we are fixing the gassers as well. good luck.

 

[shendren]

here's a tdr thread....

https://www.turbodieselregister.com/forums/showthread.php?threadid=88462&highlight=tps+rewire+kit

 

[SGreenwood]

Originally posted by c. e. linker

look on passenger side between battery and airbox. you will find a ground wire there with a grey connector in it. take the connector apart and clean it out then put together and take apart a few times. this worked for me. bad connection there.



*****************PROBLEM SOLVED*****************************



SPECIAL THANKS TO c. e. linker for the quoted post above. and to Bill from DTT transmission for his wealth of knowledge which he shared with me (THIS GUY KNOWS WHAT HE IS TALKING ABOUT )



The problem was the grey negative power connectors (grey)which come from the negative battery terminal on the passenger side of the the truck. I don't think that these are grounds to the body ? I believe that these supply negative power directly to (?) and not thru the body ground. Bill from DTT also suggested running a separate negative ground from the group / cluster body grounds to the ECM and to the PCM computers. I will be doing so very soon to save me from any trouble in the future. I wish I would have known abuot this before having to spend almost $1000. 00 on a NO COST REPAIR. So i hope this thead helps someone in the future... ... .



THANKS AGAIN TO ALL WHO HELPED.