1990 F-350, 7.3 aftermarket turbocharged. the trans has been rebuilt and the fuel injection pump has been rebuilt. the trans is shifting properly up to 3rd gear. after 3rd gear shift it goes into lock up but seems to be doing it in 2 steps and also does the same thing when in o d. the shift doesnt seem to be slipping just doing the shift in 2 steps. would the problem be in the speed sensor or somewhere else?
Any help will be greatly appreciated.

 

The normal shift for this transmission is to lock the torque converter clutch right after the 2-3 shift. It will feel like two events. It will also slip the torque converter clutch during the 3-4 shift, and relock right after the shift, once again feeling like two shifts.

If it is more noticeable than it used to be, it could be worn transmission fluid. If you have more than 30K miles, or have been towing a lot, it needs to be changed. There is an article in the Tech Articles section of this site that has a do it ourself procedure to flush out the old and install new fluid.

 

I can feel the shift from 2-3 and 3-4 without a problem. The problem i am feeling is when the converter engages, it feels like a 2 step process. I am aware of a drop in rpm during the lock-up, but that reduction is done in 2 steps, not the whole rpm change at one time. It doesnt seem to take say the whole 500 rpm change at one time. If I can say it this way:
It should be 1-2, 2-3, 3-lock up, 4-lock up
It goes 1-2, 2-3, 3-3.25, 3-lock up, 4, 4.25, 4-lock up
It seems to be finding extra ratios in there somewhere.
Maybe I need better beer.

 

That sounds like the torque converter is taking too long to lock. New fluid should help that, too.

 

Is it "shudder"? See:

http://motorhaven.autoanything.com/cgi-bin/Web_store/webshop.cgi?yearmodel=&product=SHIFTVALVE

 

I dont believe the problem is shutter. The trans was just rebuilt and had updates installed during rebuild. It seems the problem is in the electronic part. when the plus is disconnected on the fuel pump, the problem stops. It feels like the transmission is producing a half of a gear ratio during the lock up.
If I understand this correctly :
The transmission will shift 1st to 2nd without needing a lock up in the converter. In third gear the trans will be able to use the lock up of the converter and also in 4th gear (overdrive)
After shifting into 3rd gear, instead of loosing the full 500 rpm during the lock up, it looses 200 rpm and then the other 300 rpm to complete the lock up. It will also do this in 4th gear.
This has just started in the past 2 months. I can watch the tach and hear the engine speed change during all of this.

 

I was emailed this from a Ford Tech.


A comment to all you 7.3 drivers that have E4ODs. The Fuel Injection Position Lever ( FIPL ) sensor ( looks like a TP sensor ) has caused many E4OD problems. It is the potentiometer mounted on the fuel pump that sends a signal to the E4OD processor that relates to the load being run through the trans. The processor uses this info to shift gears and adjust the clutch and band apply pressures to properly handle the varying loads. Over time, and due to engine vibration, this sensor starts to lose internal contact intermittently and thus send the processor some erratic signals. This causes the processor to adjust the pressures incorrectly, the trans starts to shift erratically, and clutches and bands fail. An engineer that I knew in trans design suggested changing the FILP every 50k miles. He said you would never see or hear this from Ford, but it was his suggestion to prevent some very expensive trans repairs.

The TP (FIPL) sensor is incorporated to provide an electrical signal, which is proportional to the amount of fuel being delivered, as an input to the Transmission Electronic Control Assembly (TECA) Based on this information, the TP (FIPL) provides the proper shift scheduling and torque capacity.

Should a malfunction occur in the TP (FIPL) sensor circuit, the electrical signal sent to the TECA will be recognized as erroneous. When this out-of-specification signal is detected, the TECA will provide a high-capacity operating mode that protects the transmission from potential damage. This operating mode includes maximum TV 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.

The Ford shop manual has a procedure to set the FIPL sensor. It's fairly long and required a special guage block and the use of the Super Star Tester ( early scan tool ). I decided that this was not what the "field" needed so I called the Ford Hotline and they gave me plain and simple voltage readings at closed throttle and WOT. MUCH easier.

Closed throttle voltage = 1.1V
WOT min 0f 3.8V not to exceed 4.3V

You definitely don't want 5V at WOT. PCM would read this as a short between Reference Voltage ( 5V ) and FIPL signal and go into failure mode.

 

 

The original problem (Number 0) here is about my truck. Everyone that has looked at it agrees that it is a lock-up problem. I have been in contact with the person who rebuilt the trans and at the present time I am working with him. We thought we had the problem solved with number 6 response. When we disconnect the plug on the FIPL the trans shifts great 1..2..3. We did set the FIPL to the required voltage but the problem still exists. The fellow working on the trans had one of his contacts say to check the wires for grounds. He checked all the wires from the FILP and the speed sensor to the computer and found no bare wires. I appreciate any help I can get and really appreciate I have gotten so far from the responses to my problem. The problem is still there and the gremlins are growing!!!!!