jobunn
Elite Explorer
- Joined
- June 13, 2001
- Messages
- 854
- Reaction score
- 8
- City, State
- Santa Clarita, CA
- Year, Model & Trim Level
- '99 Sport 4x4
I finally solved my problem. My O/D light was flashing so I went through the list of possibilities as the tranny was still shifting perfectly and the fluid was clean.
First I changed the solenoid in the tranny, with no luck. Then I went to Autozone and asked for a TPS for a '99 SOHC which was about $20. After taking a few hours to get the loctite screws out I disconnected the battery and put the new TPS in.
Upon my test drive down the street I stalled out at 30mph. Drove back home, fiddled with the TPS and test drove again, this time not stalling but the truck won't downshift.
I took the TPS back to Autozone and exchanged it for another and asked them again that it had to be for a SOHC and not the OHV and they assured me and exchanged the part. After installing it still wouldn't downshift and was driving like sh@t. I was fed up now.
I took it to the dealer and asked them to check it out. They said I needed to spend $350 and have an entire electrical system check or I could do serious damage. H@ll no!!! I picked up the car immediately from them.
I finally got the brilliant idea
to check the part numbers on the TPS. Turns out I had the TPS for the OHV (F57F9B989AA), which Autozone sells for the SOHC.
Anyway I went to the dealer and bought the right TPS (F4SF9B989AA) for $35, just installed and all is fine again. Don't know if it will fix the O/D light yet, but what a relief.
Just an FYI for anyone wanting to change their SOHC TPS through Autozone.
First I changed the solenoid in the tranny, with no luck. Then I went to Autozone and asked for a TPS for a '99 SOHC which was about $20. After taking a few hours to get the loctite screws out I disconnected the battery and put the new TPS in.
Upon my test drive down the street I stalled out at 30mph. Drove back home, fiddled with the TPS and test drove again, this time not stalling but the truck won't downshift.

I took the TPS back to Autozone and exchanged it for another and asked them again that it had to be for a SOHC and not the OHV and they assured me and exchanged the part. After installing it still wouldn't downshift and was driving like sh@t. I was fed up now.
I took it to the dealer and asked them to check it out. They said I needed to spend $350 and have an entire electrical system check or I could do serious damage. H@ll no!!! I picked up the car immediately from them.
I finally got the brilliant idea

Anyway I went to the dealer and bought the right TPS (F4SF9B989AA) for $35, just installed and all is fine again. Don't know if it will fix the O/D light yet, but what a relief.
Just an FYI for anyone wanting to change their SOHC TPS through Autozone.