what do all these symptoms mean?

[guava]

This is on the 93 auto, stock.



Ok. I'm just a little baffled. I start out driving and things are just fine. After 30 minutes of hwy driving at 60 MPH, it starts feeling like its defueling... . It also feels like its the transmission slipping. As I drive, the familiar sound goes quiet like the engine isn't pulling anymore. Only for a few seconds and then comes back normal.



As I continue to drive, it starts doing it more frequently. I pulled off to check fluids and all is well. I start out again and the same behavior continues. So then I hit the button that keeps it locked out of OD. This makes the problem go away.



So, what am I missing?

 

[AlK]

My truck is a standard, but I would guess that with the auto the problem is more than likely the TPS.

 

[cerberusiam]

Sounds like the OD clutches are slipping. Does it go into OD solidly or does it kinda slide in? Generally the OD is in or out if its a TPS or pressure problem but there is always the exception. The solenoid that activates the OD shift could also be bad and leaking pressure off after things warm up or it could be time for a trans overhaul.



Internet diagnostics are so accurate.

 

[Madurski]

Except for the transmission slipping feeling it sounds like water in the fuel to me.



Ron Madurski

 

[CDegner]

This is on the 93 auto, stock.



So then I hit the button that keeps it locked out of OD. This makes the problem go away.

Your TPS is either out of adjustment or shot. Drive at 70 with it in OD then hit that button. It is probably going to feel just like it does when you have the problem occuring. You think the transmission is slipping because your RPMs come way up and your speed drops way off.



Check the stick thread at the top for how to adjust the TPS. Unless it is bad, I bet your wandering OD goes away.



Carl

 

[ak_fleming]

I had the exact same symptoms on mine. It was the TPS.

 

[guava]

Todays update

Today was warm and dry... well as warm and dry as seattle can be in January. I took the same basic drive and no problem. It does seem to be driving like a dog though. Just can't get enough power.



Tomorrow I'll rip out the TPS and try taking it apart for the fun of it.

 

[1stgen4evr]

Tps

When you remove the TPS, put the connector that engages the pump and TPS in your pocket if you plan to drive the truck. It will (the connector) shake out and it only comes with a hundred dollars of other parts. :{



James