Hi I have 91 f250 with the 7.3 and e40d transmission my question is what actually makes or tells it when to shift? Have had some problems with it not wanting to shift through the gears. Sometimes it works just fine and then the other it just gives me fits. Use to whenever it would do it I could just floor it then it would shift and be fine for a while and shift like it is suppose to but now it is not helping. The fipl is a couple of months old and got it at napa so it should be a good one. Thanks in advance for everyones help.

 

It gets information from the shift lever position sensor, the throttle position sensor and the vehicle speed sensor and I think, your rev counter. If you are having problems have you tried pulling any codes?

 

i agree with getting a fault code checked out. sounds like it's in "limp" mode. have a zf5 in mine, so not as familiar with the autos, but had a gasser with one and had a bad modulator that wasn't letting it shift right. i'm guessing the diesel autos have one as well, but don't know that for sure.
maybe this gives you another place to look.

speedrdr

 

You need to get a OBD1 code reader and follow the directions exactly when pulling the codes. be sure to floor the throttle during the engine run test or you will get a false Fuel Injection Poition Lever (FIPL) code. Before you do these tests it is highly recommended that you clean all of the wire harness connections to the transmission, FIPL, Tachometer, VSS, and your brakes. A bad connection can also cause the E4OD computer (TECA) to give bad commands to the tranny and make it shift incorrectly.
Good luck.
Jim

 

Thanks to everyone who replied waiting on getting a code scanner now.

 

You can easliy check out the FILP sensor by measuring the voltage on the middle wire- key on - engine off, it should be at about 1.1volts at idle, and 3.8 to 4.3 at wide open throttle, and a smooth even increase or decrease as its moved from one position to the other without dead spots. Just because its new doesn't mean its good. I fully agree with getting codes checked- a lot cheaper than chnageing parts until you find what wrong.

 

I'm not positive, but I think you should still have all the gears even in limp mode. Only it will shift hard into each gear.

If you are noticing it skip shift, than that could be an electrical problem, valve body problem (sticking valves) or even an internal mechanical fault. The latter is not very likely because that doesn't ususally fail intermittently, if something breaks, its broke!

 

How many miles are on it? I had the same thing with mine and well I'm getting it rebuilt. Anyway, check the connector on the passenger side of the trans. That is the one that control the servo pack. Make sure the connector is clean as mentioned above. Check the wires to make sure they aren't burnt or bare because that is close to the exhaust. Mine were bare. To get to it yo have to remove the cover plate which has two 8mm bolts holding it on. Remove the rear one and loosen the front one and it will slip off. I'm sure you have already checked the fluid, etc. Hope this helps.

 

in limp you DO have all the gears, it wont stay in/go into lockup.

 

Hi just got code scanner and tried pulling codes and can't get any. I think I have a tourque converter problem but shouldn't it throw code 62. It has 146000 miles on it and now it is not slow to shift it just when it shifts to 3rd it acts like it engages or unengages the tc because when it shifts from 1 to 2 the rpms only drop 200 to 400 but from 2to3 about 800 to 1000 then when it goes to od back to about 200 to 400. Anybody got any ideas or suggestions? Thanks alot you guys are awesome

 

If you can't get any codes you may have bad connections to the TECA( transmission electronic control assembly) or the TECA may be bad.
Jim

 

Thanks for the reply. Where is the TECA actually located? Thanks

 

The TECA is located on the firewall behind the driverside inner fender. It is low down on the wall and is hard to reach. If you decide to disconnect the wire harness from it, be careful not to bend or break the connector pins.
Jim

 

Thanks for the reply. Could you describe what it actually looks like for me? Thanks again

 

Inside the engine compartment on the fire wall you will see a long rectangular connector with a 10mm bolt going through the center of it. You have to unbolt the connector and very carefully pull it from the TECA. The actual TECA is mounted behind the driver side kickpanel next to the parking brake. If I remember correctly you have to remove the kickpanel first inorder to remove the TECA.
Jim