is this a failing torque converter
 

My torque converter has begun locking/unlocking/locking at a steady speed of 42-47 mph. It started several weeks ago, only occasionally doing it. Then yesterday it went locked/unlocked constantly everytime I approached the above speed range if I wasn't accelerating fairly hard.

I've been looking over the forum since 7:15 and have seen a couple posts related to the problem I'm having. It would appear that the most likely cause is TPS/ECM issues? In my experience, electrical problems (interference or whatever) happen almost immediately rather than over a period of weeks. Is there something else I should be looking at? Is the suncoast APPS rewire my best bet as a fix? Its hard to believe that a manufacturer would cause such a bonehead problem in their design (only a little sarcastic here).

Thanks.

RFI is most likely the problem. You may need to read some more. Isolating the alternator wire or a noise filter helps.

It definitely sounds like the apps issue that I had about a year and half ago. Do a search for apps on here, you'll find a ton of info.

Aside from just replacing the apps sensor, there are some other things you should do first. Some of these procedures may fix the problem for a good while, but you may eventually end up replacing the sensor.

A lot of people suggest different things, but I couldn't find a thread that describes all of them at once, so here you go (you should be able search for more info on any one of them in particular).

-Check and clean all battery connections really well.
-Clean and apply dielectric grease to the electric connections related to apps sensor.
-Wrap big black/brown alternator wire with lots of aluminum foil and electrical tape.
-Run an extra ground wire from passenger side battery.
-Apps reset procedure; turn on ignition but don't crank, depress accelerator very slowly and let it up very slowly, turn key off.

I did everything above, plus I ended up replacing the apps sensor itself. I haven't had a problem since.

Additionally, you can buy a noise filter, play with the apps sensor voltage, and then there's this one: https://www.atsdiesel.com/PDF/120505...%2047%20RE.pdf

Also, I saw that somebody on here was selling an aftermarket sensor for a really good price--I wish they had that when I bought mine for $400.

Good luck!

Thanks for the help. I'll go try that at lunch. The atsdiesel page looks more indepth than the suncoast one, so I'll give it a shot.

Un hook the alternator and go for a drive.
If it is electrical noise from the alt. it will be gone.
Clean all grounds and filter the signal wire at the computer. Or even at the alt.

Repeat of j-fox advice. I also fought your issue. It is intermidatent as wiring or capicator loses efficency.

I love it when its something so ridiculously easy.

On the advice of the guys who said to just disconnect the alternator I was taking a look at it and realized the wire bundle that passes over the alt (with the alt wire in it) was contacting the alt enough to rub a shiny spot on it. I manipulated the wires out of the way and voila, I have been unable to get it to repeat the problem. BTW, this was on the return trip after I had confirmed the problem was still present.

I'm hoping that the wire being in contact with the alternator case was enough to cause the voltage spike (the elec field too).

Thanks for the suggestions, and as a precaution for the future, should I go ahead and ground the ECM PCM APPS as per the atsdiesel fix above?

More info - possibly
 

The first 'sticky' in the forum is 'Common problems and How to.....' and one of the first posts is about this problem. Happened with my '99. The fix was just cleaning and re-greasing some connectors.

ats filter fixed mine! worth the $100 after shipping

A new TPS fixed mine.