Tranny or ignition?

[RGK]

A stange problem just started on my '97 SOHC. When driving hilly roads and the tran needs to downshift going up as hill, it seems to hunt for a gear, if the throttle is pushed hard no problem. Fluid is good and changed every 25k miles. On normal roads, no problems. Any ideas on what to check? Thanks

 

[ALYZ1FLR]

Sounds like the tps.

Back probe and do the key on engine off test. Look for dead spots at the part throttle range.

 

[RGK]

As I recall '95 plus has OBD-II, no KOEO test possible. I think its the OD being confused. Will try with it off. Thanks

 

[Blee1099]

OBDII was installed in our Explorers starting in 1996..

 

[ALYZ1FLR]

Let me clairify!

With the key on and the engine not running... Back probe the TPS. It should have no dead spots. The TPS signal is one of many inputs controlling overdrive.