Mysterious E4OD Poblem(s) - Getting Worse - Help!

[peacetank]

Ok so my old beater econoline van with the 7.3L IDI and the E4OD is starting to worry me. I call it a beater but I want you to realize that doesn't mean that I neglect it. It just means that I don't put any money in it other than fixing what's broke and regular preventative maintenance.

So I think I either have an electrical issue or a torque converter issue.

The transmission has always exhibited the following strange behaviors:
-When the torque converter locks up in overdrive the engine RPM's always spike first before it locks. (low line pressure maybe???)
-Sometimes the tranny randomly goes into "limp mode" (the O/D light starts flashing, the line pressure goes all the way up and it shifts hard, - it actually shifts pretty good when this happens). Then it will randomly go back to regular mode. It seems that this happens more often after extended highway driving.
-On several occasions the torque converter has not locked up at all durring a trip, but everything else is normal.
-Once I was driving and everything was fine. I put it in park then went to go again and it did not want to move. Reverse worked fine. Then it fixed itself and it has been fine for several thousand miles since.

So, you can see it has its issues, but they have never been enough for me to park it. **Also note that it has new fluid & filter with lucas additive and an aftermarket cooler and upgraded larger cooler lines**

Now today, the following issues started happening:
-As I was driving along the highway, the torque converter unlocked. Then it tried to lock back in several times, but failed. Then I noticed that it would consitantly try to lock every five seconds while I was driving down the highway. (electrical???) But it never locked back up. Then I drove it again, and the torque converter locked up for a while like normal, then started acting up again. On another drive, it was locked up in overdrive, I let off the gas, then rolled back into the throttle, and nothing. The engine just reved. - Not a good feeling. I took it out of overdrive and it engaged in gear, then put it back in overdrive and it was fine.

I have replaced both wiring harnesses, but not the range switch. What about the TPS? Or do you think the torque converter is just shot? Or is my line pressue too low?

Thanks for you help, THIS IS WHY I LIKE STANDARDS!!!!!!!!!

 

[94f450sd]

while you and many others like standards the nice thing about that e4od is it will tell you whats wrong with it.take it to a shop and have a scanner put on it to get the codes.

my old 94 did what yours is doing a couple times.then fixed itself.never had a problem till i worked it one night moving cars.everything was fine till i pulled into the store up the street from my house.had to wait for a parking spot,car finally moved and i went to pull in the spot.had nothing.reverse worked perfect but had no forward unless i held the throttle to the floor.tranny shop said it cracked the tranny case.

 

[OLDBULL8]

You are referring to the 94 E350.
Torque convertor and line pressure has no effect on what you are experiencing.

The VSS can. Pull it out and clean off. Top of rear diff.
Wireing to VSS.
The TCP can. A long shot tho.
Defective EEC relay.
Corroded connection to the solenoids can. Pass side of the tranny.
Corroded connection to range switch can. Drivers side.
In Limp mode, you only have 2nd and reverse gears. Hard down shift and RPM spike.
Disconnect the battery B+ cables to erase any codes, drive it until you have trouble again. Then get the codes read. Don't waste money just replacing parts.

 

[trackspeeder]

Check the TPS (FIPL) Make sure its within range.

Most important, have the codes pulled. It will save you some aggravation.

 

[oldmisterbill]

I agree with everyone here -except the first thing I would do especially with intermittant sypmtons ,is to clean (I mean CLEAN!) every electrical connector it the system. Then use some diaelectrice sylicone past & pack every connector. I had torque convertor lock & random unlock once and that is what I did .The whole trans worked better after & because I coated the connectors ,I have never had to go back there again.

 

[peacetank]

Thanks guys I will be pulling the codes tomorrow. Also, I may have been misleading when I said "limp mode." What I was trying to say is that the light begins flashing and then it shifts hard, but all the gears do work fine.

 

[Compu Doc]

Check the computer connections also. Mine had two broken pins. On the van you will find the computer near the heater core. Also make sure that your heater core is not leaking because if it is it will get the computer wet and water on the brain is not good.

 

[trackspeeder]

Thanks guys I will be pulling the codes tomorrow. Also, I may have been misleading when I said "limp mode." What I was trying to say is that the light begins flashing and then it shifts hard, but all the gears do work fine.

When the OD Off light flashes, the tranny goes into High Pressure mode. The reason for the hard shifting. Most people call it "limp mode"

 

[itsacrazyasian]

+1 on it being a bad vss on the tranny or bad TRS. I just chased one in the shop. replaced it with a customer supplied TRS, help but still would neutral out when driving and the OD light would flash. Replaced it with a Ford unit and all is well. The truck going in and out of lockup was the VSS on the same truck.

 

[sak778]

Can the VSS be bad if the speedo works fine? mine wont lock up at all ever, Among other things. What ido you mean by TRS? u mean FiPLS or TPS?

 

[GRU]

if by chance you do happen to need another tranny i do have one im trying to get rid of. youre only in wheeling i can deliver it too if need be. just throwing this out there.

 

[trackspeeder]

Can the VSS be bad if the speedo works fine? mine wont lock up at all ever, Among other things. What ido you mean by TRS? u mean FiPLS or TPS?

TRS Transmission Range Sensor. The sensor is on the left (drivers) side of the tranny.

When they go bad the tranny will just go into neutral for no reason. Down shift at speed is another issue they have.

If the converter doesn't lock up at all. Electrical end would be no signal to S3 solenoid, or S3 solenoid is bad.

Mechanical end would be damaged seals, or stuck control valve.

 

[sak778]

Ok so TRS is the neutral safty switch. I'm currently swapping out my under hood and transmission harness for one thats not all chewed up by critters nesting under the hood. Hopfully that will solve most of my problems.
So as long as the speedo works the VSS is good to go right? Thanks, Sean


YMMV