Can a boost leak cause erratic and or harsh shifting in an e4od?

[headhunter38]

1994 f350 factory turbo e4od. It has harsh and erratic shifting that I am trying to narrow down. Could boost leaks contribute to it? Is the computer expecting a certain amount of power at given rpms that when not there can cause shifting issues, ie is the factory turbo transmission computer tuned differently than for the NA motor? Im wondering this because I know i have boost leaks and am wondering if I should fix them before trying to work on the shifting issues.

 

[DaveBen]

There were NO Factroy Turbo trucks back in 1994. This is an add-on. Do you see who made the turbo kit on the turbo? Thay will be the people you will want to contact.

 

[89Laredo]

There were NO Factroy Turbo trucks back in 1994. This is an add-on. Do you see who made the turbo kit on the turbo? Thay will be the people you will want to contact.

Uhh.. yes there was?



Anyway... I know nothing about the e40d or how it operates but have you checked your third brake light and FIPL.

 

[DirtyWood]

There were also factory turbo trucks in 1993, too. I don't think the E4OD gives a hoot about boost or the lack of it.
Hopefully the erratic shifting is due to external problems.

Is the tachometer functioning properly? A brand new tach sensor will often read about 2400 ohms between the two prongs on the connector--the closer to 2k or 3k ohms means the sensor may be getting a bit worn.

How's the Throttle Position Sensor reading? Should be about 1 to 1.2v at idle and close to 4.0v at WOT but not over 5v.. Ground wire needs to be solid and not reading any voltage. Reference wire should read 5v--mine reads 5.05v and it's fine. After hooking up a multimeter to the TPS move the throttle slowly from idle to WOT and see if there are any dead spots where the voltage jumps instead of smoothly increasing.

Speedometer working properly? The VSS sensor on top of the rear diff might be dirty or failing.

I don't have the same dash as you but maybe the PSOM is tied in somehow and the transmission control module isn't getting a clean signal.

Fluid level good? Clean fluid nice and red?

 

[headhunter38]

Anyway... I know nothing about the e40d or how it operates but have you checked your third brake light and FIPL.

FIPL is a brand new NTK sensor. I have been playing with its adjustment since installing transgo shift kit. Ill check the brake light.

 

[DirtyWood]

The last TSB issued by Ford regarding the FIPL/TPS mentioned 1.2v as the ideal idle voltage. The upper range seems to be much less important than the idle setting. I've tried multiple TPS and some maxed out at 3.65v WOT while others maxed out at 4-4.2v WOT but they shifted the same. So far I've found that setting engine idle at 750 RPM in Park and TPS at 1.2-1.23v at idle has yielded the best performance with a firm shift.

 

[DisasterPastor]

First of all, Ford absolutely had factory turbo. Started in i think 93 but definitely in 94. I own one and it's been in my family since 96 and somewhere i have the window sticker proving it.

It has nothing to do with boost leaks.

Here's the things I've done over the years with same issue. First your throttle position sensor needs checked. Very easy to do.

Next, there's a speed sensor in the rear end, replace it, it's easy and cheap.

Also the tach sensor, easy and cheap.

If that doesn't solve it you may have internal issues.

I'm attaching my TPS notes.

If you have any questions email is best for me. "[email protected]"

 

[headhunter38]

The last TSB issued by Ford regarding the FIPL/TPS mentioned 1.2v as the ideal idle voltage. The upper range seems to be much less important than the idle setting. I've tried multiple TPS and some maxed out at 3.65v WOT while others maxed out at 4-4.2v WOT but they shifted the same. So far I've found that setting engine idle at 750 RPM in Park and TPS at 1.2-1.23v at idle has yielded the best performance with a firm shift.

I adjusted the tps back to around there and its actually shifting even worse. Shifts around 3100 rpm and very harshly. More violent than before when it was adjusted to around 0.87. I wonder if the pump is damaged from when I tried moving it the parking lot before i discovered it had very little fluid in it. I think i am to read the line pressure. Also I noticed when it was previously adjusted to 0.87 there was a few days when it was cooler out that it shifted really good in the beginning of driving and then as it warmed up it started to get harsh again. I suspect that the fluid pressure was higher as it was colder and then pressure dropped as it warmed up. If that holds true I might try like 2 or 3 bottles of lucas stop slip to thicken it and see how that affects it before ripping it apart to put in a new pump.

 

[DirtyWood]

I adjusted the tps back to around there and its actually shifting even worse. Shifts around 3100 rpm and very harshly. More violent than before when it was adjusted to around 0.87. I wonder if the pump is damaged from when I tried moving it the parking lot before i discovered it had very little fluid in it. I think i am to read the line pressure. Also I noticed when it was previously adjusted to 0.87 there was a few days when it was cooler out that it shifted really good in the beginning of driving and then as it warmed up it started to get harsh again. I suspect that the fluid pressure was higher as it was colder and then pressure dropped as it warmed up. If that holds true I might try like 2 or 3 bottles of lucas stop slip to thicken it and see how that affects it before ripping it apart to put in a new pump.

Any codes to pull?
The 1.2v came from this TSB, https://www.ford-trucks.com/forums/...-and-adjustment-diesel-applications-only.html

I've tried both a Motorcraft NOS TPS at 1.2v and Standard Motor at 1.2v and definitely not harsh shifting. My truck came already equipped with the Banks TransCommand which supposedly raises line pressure.

Any difference in shifting behavior in 2nd as opposed to Drive?
Maybe check the solenoid pack.

 

[headhunter38]

Any codes to pull?

I finally found my innova obd scanner and pulled codes. I got codes 23 and 14. 23 from what I understand means nothing really as I didnt press the pedal while reading the codes. From the manual code 14 indicates "Engine RPM sensor circuit fault (Diesel)". Could that be due to my tps currently being adjusted to .98v or so?

Any difference in shifting behavior in 2nd as opposed to Drive?

I havent done that yet. Ill test that out.

 

[headhunter38]

First of all, Ford absolutely had factory turbo. Started in i think 93 but definitely in 94. I own one and it's been in my family since 96 and somewhere i have the window sticker proving it.

It has nothing to do with boost leaks.

Here's the things I've done over the years with same issue. First your throttle position sensor needs checked. Very easy to do.

Next, there's a speed sensor in the rear end, replace it, it's easy and cheap.

Also the tach sensor, easy and cheap.

If that doesn't solve it you may have internal issues.

I'm attaching my TPS notes.

If you have any questions email is best for me. "[email protected]"

Tps is new and im making adjustments to it. The speed sensor tested out good. I checked both from the test port and with it removed, also cleaned it. I have not tested the tachometer sensore yet. That is the one on the side of injection pump cover right? I fear that it is internal issues and likely from the pump.

 

[DirtyWood]

Yeah the tach sensor is the big 1" or so nut with 2 wires on the pump gear cover.

I don't think the TPS setting would relate to a code 14 because the TPS "out of range" code is different.

I'm unfamiliar with code 14 but a clean tach signal is critical input for the trans computer. I found another old post here regarding a code 14 and it turned out to be the tach sensor. Classic Diesel Designs claims to have Motorcraft sensors but as far as I can tell they are just marked up Dorman sensors--like 100% mark up.

 

[Smitty 90idi]

Tps is new and im making adjustments to it. The speed sensor tested out good. I checked both from the test port and with it removed, also cleaned it. I have not tested the tachometer sensore yet. That is the one on the side of injection pump cover right? I fear that it is internal issues and likely from the pump.

Don’t adjust the tps. Set it at which ever voltage you prefer of the 2 suggested and forget about it. When everything is working right you can chose which voltage gives you the shift points you prefer. That isn’t the problem here. It won’t cause the symptoms. The tps has nothing to do with the tach I’d be looking at the tach signal. Or bad grounds. Ground cause all kinds of issues as does old wiring in general. Do you have led brake bulbs by chance? 3rd brake light working? If so and all grounds are good I’d start at the rpm pick up. Is it getting power in. 0.5v AC AT IDLE. also should read around 2500ohs. If that passes your going to move to the computer and make sure you have good continuity from the tach pick up to the computer.



Any difference in shifting behavior in 2nd as opposed to Drive?
Maybe check the solenoid pack. If you put it in 2nd it will not shift at all. It will start and stay in 2nd.

 

[headhunter38]

I replaced the tachometer sensor with a dorman unit. The old ones wires were frayed and barely hanging on. Strangely though the tachometer seemed normal. It definitely made a difference and shifts much better.
I do have led brake lights and one of them is out. Previous owners went and installed leds all the way around. I bought some regular ones and will put them in and see how that changes it.

 

[u2slow]

Something else that makes a E4OD spazzy is a bad speedo signal from the rear end. Is ABS acting up too?