How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Scottdagoalie Your Own Question
Scottdagoalie, Senior Master Tech.
Category: Ford
Satisfied Customers: 1940
Experience:  30 years with Ford dealers
Type Your Ford Question Here...
Scottdagoalie is online now
A new question is answered every 9 seconds

I have a 1994 Ford F-250 with the 7.3L Turbo Diesel not a powerstroke

This answer was rated:

I have a 1994 Ford F-250 with the 7.3L Turbo Diesel not a powerstroke i had been having tranny issues the over drive light would blink and it would change gears erratically i was told by a mechanic that it was probably the tranny solenoid pack so i changed that out and now i don't have 1st gear at all and it wont downshift out of overdrive when you come to a stop, i did a little research about people who have had the same problems and most of them it ended up being the speed sensor. So my intention is to change out the speed sensor,camshaft position sensor and throttle position sensor pull the newer solenoid and clean the valve body and put the old one back in but im not sure where these 3 sensors are exactly located i need a specific location or a diagram of some kind to help me locate them please need an answer asap

HiCustomer Thank you for asking your question on JustAnswer.


The speed sensor is located near the tailshaft of the transmission.

Vehicle Speed Sensor (VSS) 9E731:
Description: The vehicle speed sensor is a variable reluctance sensor that sends an AC/frequency signal to the powertrain control module . The vehicle speed sensor signal is used by the powertrain control module to calculate vehicle speed in mph.
Transmission Function: Used as an input in determining shift scheduling and Electronic Pressure control.
Symptoms: Harsh engagements, firm shift feel, abnormal shift schedule; unexpected downshifts may occur at closed throttle, abnormal torque converter clutch operation or torque converter clutch engages only at wide-open throttle. May flash transmission control indicator lamp.



The Throttle position sensor on your diesel is located on the injector pump.


Throttle Position (TP) Sensor 9B989:
The throttle position sensor is used on E-250-350, F-250-350, and F-Super Duty vehicles equipped with a 7.3L diesel engine and an E4OD automatic transmission. The throttle position sensor is a potentiometer attached to the fuel injection pump and is operated by the throttle control lever .
The throttle position sensor is incorporated to provide an electrical signal, which is proportional to the amount of fuel being delivered, as an input to the powertrain control module . Based on this information, the powertrain control module provides the proper shift scheduling and torque capacity.
Should a malfunction occur in the throttle position sensor circuit, the electrical signal sent to the transmission electronic control assembly will be recognized as erroneous. When this out-of-specification signal is detected, the transmission electronic control assembly will provide a high-capacity operating mode that protects the transmission from potential damage. This operating mode includes maximum electronic pressure control pressure, resulting in harsh upshifts and engagements and a singular shift schedule regardless of accelerator pedal position, resulting in the 1-2, 2-3 and 3-4 shifts occurring at a speed commensurate with a heavy (but not wide open) throttle setting.
Should harsh or poorly scheduled shifts be encountered, perform Key-On, Engine-Off (KOEO) On-Board Diagnostics to determine the appropriate repair to be performed and correct as necessary before proceeding. Should it be necessary to service the throttle position sensor


The cam sensor is not shown on a non-turbo diesel and would not affect transmission operation.


I have worked on two diesel transmissions this week ,like yours, and both of them had faulty PCM's.I recommend removing the PCM and inspect for possible water damage.Both of the trucks that I saw had corrosion on the outside of the PCM case,and had shifts with fault codes stored for speed sensor,throttle posisition sensor and control pressure faults.The PCM is located under the hood near the drivers side fender.

Scottdagoalie and other Ford Specialists are ready to help you