E4OD MLPS wiring

[Compu Doc]

Anyone have a wiring diagram for 1991 of the MLPS?.

My truck is having it's tranny completely rebuilt and the shop where it has been for over a week replaced the MLPS in addition to the other work. whether they have it wired right I have no idea because the truck is still in the shop with problems. I know their is an upgraded MS for these and maybe they screwed something up.

The other day I went to pick up the truck and as we were approaching the shop I see my truck leaving the parking lot. The owner of the shop took it for a test drive and when he came back said they still have problems because it is not shifting right and sometimes starting off in 5th gear.

The one thing they did not do when they pulled the trans was pull the battery cables off so even with the tranny out the tranny computer was getting voltage to it. The owner of the shop had thought that the battery switch disconnected everything and I had told him that it does not because the clock on the radio keeps time and the computer would have to relearn every time the truck went on the road and it never had to do that.

I have the Ford shop manual but it does not have the MLPS wiring diagram and what the color codes are. although step number 1 for removing the transmission is to remove the negative battery cables which was never done by the so called technician.

 

[OLDBULL8]

You don't have a 5th gear. 1 2 3 OD
The MLPS should just be a pluggin.
Is your speedometer cable driven? If it is then the VSS is integeral with it. If not then the VSS is on the rear axle.
To set the MLPS for neutral, adjust it so both marked lines, line up.
Did anyone mess with the FIPL? Miss adjusted would cause FU shifting.
Sounds like they put the wrong MLPS on if they cut the wires.
Me thinks they don't know what the hell they are doing.

 

[Dsl_Dog_Treat]

Will this work??

 

[david85]

1991 is a cable driven speedometer with 1992 and up being the change over year to electronic.

The MLPS sensor is not supposed to be rewired under any circomstances and is replaces as an assembly with the wiring in the truck simply plugging into it. There is no reason for anyone to tamper with the individual pins.

Starting off in 4th gear is usually a power supply issue to the computer or solenoid body. The bulkhead connector on the passenger side of the transmission is often damaged by people that do not read the shop manual on how to properly disconnect it from the transmisssion. This can result in poor contacts that are supposed to allow the shift solenoids operate the different gears that the TEC commands. With no power getting to the shift solenoids, you end up with a 4th gear start even at 0 MPH.

The other fairly common problem is the TEC (transmission electronic control) relay not delivering enough power to the TEC itself. This can prevent the shift solenoids from switching on and off reliably and again, resulting in a 4th gear start.

One last thing is the solenoid body itself could be shot. It doesn't happen very often but sometimes does.

 

[Compu Doc]

1991 is a cable driven speedometer with 1992 and up being the change over year to electronic.

The MLPS sensor is not supposed to be rewired under any circomstances and is replaces as an assembly with the wiring in the truck simply plugging into it. There is no reason for anyone to tamper with the individual pins.

Starting off in 4th gear is usually a power supply issue to the computer or solenoid body. The bulkhead connector on the passenger side of the transmission is often damaged by people that do not read the shop manual on how to properly disconnect it from the transmisssion. This can result in poor contacts that are supposed to allow the shift solenoids operate the different gears that the TEC commands. With no power getting to the shift solenoids, you end up with a 4th gear start even at 0 MPH.

The other fairly common problem is the TEC (transmission electronic control) relay not delivering enough power to the TEC itself. This can prevent the shift solenoids from switching on and off reliably and again, resulting in a 4th gear start.

One last thing is the solenoid body itself could be shot. It doesn't happen very often but sometimes does.

Supposedly the solenoid body was replaced. The MLPS was replaced as well and their is an upgrade from Ford because the old style connector would allow water to get into the connector. Whether or not they got the part from Ford or another supplier I do not know but I will be asking that tomorrow when they call with the status. Hopefully they got the problem resolved by then.

The other day the owner of the shop had said sometimes it starts in 4th and sometimes its shifting like it should so who knows. All I do know is that when it was brought in their it did not have that problem. The problem it was having is it would have to be put into second to start off and manually be placed in D for the third gear. It would not go into fourth nor would the TC lock up as it should have. It would also sometimes neutral out.

In bringing it to one shop they did a code scan and they came up with a few codes that indicated a slipping TC and a few slipping gears. They were not able to do anything as they did not have a lift that would support the weight of the truck. Another place came up with the same codes and both times the codes were read I seen them myself but the second place only was willing to give a 12.000 mile/12 month warranty and for the money they wanted I did not feel the warranty was good enough so this place it is at gives a 50.000/36 month warranty and that's why I went with them. All I know is they did not disconnect the batteries before they took out the trans nor did they probably disconnect them before putting the trans that they took out was rebuilt and probably put it back in without disconnecting the batteries.

The OD light does not work either at this point and it did before it went in.

 

[Compu Doc]

Will this work??

Thanks, I came across the same diagram although I do not know if it is for a 1991 model year. The truck is still in the shop so I have no way to confirm if the wires are the same colors in the description.

 

[trackspeeder]

The second diagram from the bottom is the one you want.

Your tranny shop should have upgraded to the 95 range sensor. (The bottom diagram)

If they up graded the sensor and connector. There is a good chance the pins are not seated or incorrect locations.

 

[fury9]

go get your truck back- unless they have a hundred thousand mile warranty, I would be pretty effin pissed.

 

[Compu Doc]

go get your truck back- unless they have a hundred thousand mile warranty, I would be pretty effin pissed.

I'm not to happy right now about the situation. It's the only vehicle I have so tomorrow when I talk to them I am telling them they have a choice if they can't complete the job today. The choices they have are for me to rent a car and take the rental off their bill or lend me a car. Either way it will be until the job is complete. I have places to go and can't get their.

 

[david85]

I think only ford offers the 3 year / 100 000 mile warranty. Then there is the BTS transmission but thats in a price league of it's own.

Still think its a loose connector or other form of power supply issue. The overdrive light issue strengthens my suspicion of that.

Surprised they didn't give you a courtesy car.

 

[trackspeeder]

Have them check the solenoid pack. If that checks out, do a line pressure test. Low line pressure will cause it to start in fourth.

 

[Compu Doc]

Well I stopped by the shop today. They are having an E4OD computer over nighted from some company in Texas. Today I stopped by and they pulled the computer. It was located near the heater core which recently took a dump and was replaced at another shop a few weeks ago. So I think this was the problem that lead to the trans failure. Computers and water do not mix so why did Ford ever put the computer near a source of water that could rupture causing a failure?

It must have been an engineer and I have always said Engineers are A$$holes and this only proves it. The least they could have done was seal the computer in rubber so if it got wet it would not damage it. Besides the computer being hit with water their were two broken pins.

Seems like the failure of the trans was caused by a bad computer. Hopefully all will work out as I have a hotel reservation for Friday in Lancaster PA for an event I am attending Saturday so the trans will get a nice workout if the computer solves the problem. If it does not then I am going to have them revisit the MLPS connector but one thing for sure the computer looked like it was found in a stream so I didn't even try to argue about them causing it to go bad by not disconnecting the batteries.

Now that we know the location of the computer of the E350 is near the heater core where is the computer located on the F series trucks with the E4OD?.

Oh well at least if it works out tomorrow I wont have to shift from 2nd manually to D to get third gear and the rebuilt trans has a billet steel multi disc torque converter and an upgraded valve body with a shift kit which is what I told them I wanted besides the rebuild.

 

[GenLightening]

On the trucks is located behind the driveside kick panel.

 

[trackspeeder]

Well I stopped by the shop today. They are having an E4OD computer over nighted from some company in Texas. Today I stopped by and they pulled the computer. It was located near the heater core which recently took a dump and was replaced at another shop a few weeks ago. So I think this was the problem that lead to the trans failure. Computers and water do not mix so why did Ford ever put the computer near a source of water that could rupture causing a failure?

It must have been an engineer and I have always said Engineers are A$$holes and this only proves it. The least they could have done was seal the computer in rubber so if it got wet it would not damage it. Besides the computer being hit with water their were two broken pins.

Seems like the failure of the trans was caused by a bad computer. Hopefully all will work out as I have a hotel reservation for Friday in Lancaster PA for an event I am attending Saturday so the trans will get a nice workout if the computer solves the problem. If it does not then I am going to have them revisit the MLPS connector but one thing for sure the computer looked like it was found in a stream so I didn't even try to argue about them causing it to go bad by not disconnecting the batteries.

Now that we know the location of the computer of the E350 is near the heater core where is the computer located on the F series trucks with the E4OD?.

Oh well at least if it works out tomorrow I wont have to shift from 2nd manually to D to get third gear and the rebuilt trans has a billet steel multi disc torque converter and an upgraded valve body with a shift kit which is what I told them I wanted besides the rebuild.

Water on the brain is not a good thing. You might have found your problem.

 

[Compu Doc]

Water on the brain is not a good thing. You might have found your problem.

I'm beginning to think that maybe water on the brain is not only affecting the computer but maybe the shop owner as well. Yesterday he told me that the company he ordered the computer from only does computers and nothing else. He also told me that they are shipping him one over night by Fed Ex. Fed Ex delivery time for overnight is by 10am so I called him today at 2:39 and he told me that UPS just left 15 minutes ago and dropped it off. He also said he would call back in 60-90 minutes. Two and a half hours later after him not calling back in his 60-90 minutes I call him and the new story is UPS has not arrived yet and that he called UPS but they could not tell him the status of the shipment. He then says that UPS might be their later.