The Diesel Stop banner
1 - 16 of 16 Posts

· Registered
Joined
·
29 Posts
Discussion Starter · #1 ·
Greetings all. I have a 2wd 1993 f250 with the 7.3idi and e4od combo.

My trans lost torque converter lockup. I narrowed it down to either bad torque converter or bad pump (yes, I checked every one of the 27 other dumb things it could be). I didn't want to spend the money on replacing when I knew one of the two was likely fine, so not knowing for sure which it was, I bought an entire used trans with converter off of marketplace that supposedly worked fine and only came out of the truck due to a zf5 swap. I was sent videos of it running/driving, but the videos didn't tell the full story and were misleading come to find out.

I installed the trans and it was messed up too.... it has some strange stuff going on. Problem number one: when you put it in D, and take off just like you normally would, the truck is very very sluggish and doesn't want to move, it feels like when you try to take off in a manual transmission vehicle in 2nd or 3rd gear. It eventually gets up to speed, it goes through gears and the torque converter locks in, but it is missing one feelable shifting event.

Problem two: to see if it had all the gears but somethings was just messed up with the D setting, I figured I'd start in 1, and shift up manually. Doing this, the truck takes off, accelerates, and feels like a proper normal functioning e4od should. But when I shift into 2, there is no shift, nothing happens. It just keeps accelerating in whatever gear it's actually in. When I shift into D from 2, there is a shift. Also, if I skip 1 and take off in 2, it feels and acts the same as if I were to take off in 1.

The truck is drivable like this, I have driven it probably 100ish miles under these conditions. It never slips, or does anything whacky. Two times, though, I have gotten the flashing light on the gear selector. The first time I just reset it by disconnecting the battery cables. It didn't blink again for probably 60 miles. This second time the light began blinking, I went to read the codes, but my code reader is messed up and would not initiate the test when I push the test button...

So any idea what's going on here? Am I missing a gear or something? I'm not sure what route I should take here, but between the two messed up trans's, I should be able to get one working with what I have. I've thought about taking the converter out of the current installed trans and just putting that in my old trans. But I'd hate to do that and it be the pump that was messed up on the old one, not the converter. I've thought about putting the current installed converter and pump into my old trans, but I don't want to put that pump in if the problems I'm currently experiencing are pump related. I've thought about just buying a New pump and new converter and putting them in my old trans, but then I'd have waisted a bunch of money on the used trans...

Thoughts?
 

· Super Moderator
Joined
·
9,138 Posts
Problem number one: when you put it in D, and take off just like you normally would, the truck is very very sluggish and doesn't want to move, it feels like when you try to take off in a manual transmission vehicle in 2nd or 3rd gear. It eventually gets up to speed, it goes through gears and the torque converter locks in, but it is missing one feelable shifting event.

Problem two: to see if it had all the gears but somethings was just messed up with the D setting, I figured I'd start in 1, and shift up manually. Doing this, the truck takes off, accelerates, and feels like a proper normal functioning e4od should. But when I shift into 2, there is no shift, nothing happens. It just keeps accelerating in whatever gear it's actually in. When I shift into D from 2, there is a shift. Also, if I skip 1 and take off in 2, it feels and acts the same as if I were to take off in 1.
No, it does not go through all of the gears. What you are describing is limp mode. In this mode when in D the trans only operates in fourth gear with the torque converter unlocked. If you move the shifter to 1 or 2 you will get second gear only. This is exactly what you have described.

This second time the light began blinking, I went to read the codes, but my code reader is messed up and would not initiate the test when I push the test button...
You probably have a power problem to the computer. Quite often the power relay fails and the computer doesn't power up. If it works intermittently it will do exactly what you are describing.

So any idea what's going on here?
You have an electrical issue powering the computer, or possibly just the trans. With the key on, see if the computer has +12v on pins 37 and 57.
 

· Registered
Joined
·
29 Posts
Discussion Starter · #3 ·
No, it does not go through all of the gears. What you are describing is limp mode. In this mode when in D the trans only operates in fourth gear with the torque converter unlocked. If you move the shifter to 1 or 2 you will get second gear only. This is exactly what you have described.


You probably have a power problem to the computer. Quite often the power relay fails and the computer doesn't power up. If it works intermittently it will do exactly what you are describing.


You have an electrical issue powering the computer, or possibly just the trans. With the key on, see if the computer has +12v on pins 37 and 57.
Where are these pins that I would test them? You mean the pins of the connector that goes into the transmission?
 

· Registered
Joined
·
29 Posts
Discussion Starter · #4 ·
No, it does not go through all of the gears. What you are describing is limp mode. In this mode when in D the trans only operates in fourth gear with the torque converter unlocked. If you move the shifter to 1 or 2 you will get second gear only. This is exactly what you have described.


You probably have a power problem to the computer. Quite often the power relay fails and the computer doesn't power up. If it works intermittently it will do exactly what you are describing.


You have an electrical issue powering the computer, or possibly just the trans. With the key on, see if the computer has +12v on pins 37 and 57.
And if this is the pins you're talking about, when looking up what pins are what, im not seeing a 37 anywhere, im seeing a 32 and 33.

It's saying 57 is ground, and there's two 32. One 32 says its power (hot in start) and the other says starter relay feed. I'm super confused. Some of the diagrams that come up on the internet has one of the 32 as 33.

Do you think it'd make more sense to just put my old trans back in that was not in limp mode? I'm really leaning towards there's something wrong with this current one. I don't think anything else could have messed up with the truck while it was sitting between dropping the old one and putting the new in.
 

· Super Moderator
Joined
·
9,138 Posts
I'm sorry, I wasn't clear. Pins 37 and 57 are on the PCM, not the transmission connector.
 

· Registered
Joined
·
29 Posts
Discussion Starter · #6 ·
I'm sorry, I wasn't clear. Pins 37 and 57 are on the PCM, not the transmission connector.
Where is the pcm located? From what I've seen of pictures of it, it has a ton of pins. How do you tell which pin is what? And lastly, I assume it's plugged in, I would be testing the corresponding wire coming from the particular pin, correct?
 

· Registered
Joined
·
29 Posts
Discussion Starter · #7 ·
I'm sorry, I wasn't clear. Pins 37 and 57 are on the PCM, not the transmission connector.
Ok, I found the pcm after some googling. I was getting mixed answers as to its location. There are some numbers on the plastic face of it, but not many. I'm not sure if they're corresponding to the wires or not, but 37 and 57 aren't there. I Googled pcm wire diagram for the truck, but am only getting ones for the direct Injected turbo ones. Do you know if that'd be the same as this one?
 

· Super Moderator
Joined
·
9,138 Posts
Pin 37 and pin 57 are the two red wires. They are at one end of the connector. The DI Turbo PCM is very different than yours. Check for +12v with the connector plugged into the PCM and the key on.
 

· Registered
Joined
·
29 Posts
Discussion Starter · #9 ·
Pin 37 and pin 57 are the two red wires. They are at one end of the connector. The DI Turbo PCM is very different than yours. Check for +12v with the connector plugged into the PCM and the key on.
Awesome, thanks a ton! The two solid red right next to eachother? Also, do I do positive test lead to the wire and negative test lead to any ground?

I remember on one other thing I checked a while ago on the trans plug, it was a positive fed ground or something, I can't recall exactly. I just know it wasn't positve test lead to one wire and negative lead to any ground.

Thanks!
 

· Super Moderator
Joined
·
9,138 Posts
Yes, the two red wires next to each other. Put the positive lead to each of those wires and the negative lead to the ground.
 

· Super Moderator
Joined
·
9,138 Posts
Chances are the solenoid body is bad. But that's just a guess. You could check the resistance of the two shift solenoids to see if they are really bad. I don't have the wiring diagram of the solenoid body.
 

· Registered
Joined
·
29 Posts
Discussion Starter · #13 · (Edited)
Chances are the solenoid body is bad. But that's just a guess. You could check the resistance of the two shift solenoids to see if they are really bad. I don't have the wiring diagram of the solenoid body.
Next question for you... I'm changing out that solenoid. Behind the solenoid is some sort of gasket (the gasket or whatever is not just forthe solenoid, it's everything that's there when the pan is removed). It looks like it's either some sort of hard rubber or plastic. There's a couple of sections where the black material (rubber or plastic) is missing. Are those small sections missing a big deal? Or is it imperative I replace this gasket?

Thanks!
 

Attachments

· Super Moderator
Joined
·
9,138 Posts
Those missing parts of the gasket might be the reason you are having these problems. It is more than critical.
 

· Registered
Joined
·
29 Posts
Discussion Starter · #15 ·
Those missing parts of the gasket might be the reason you are having these problems. It is more than critical.
I also found out different solenoid packs won't work in different years. So it was/coulda been that too.

Anyway, I replaced that gasket and I swapped the solenoid out. I think it's good! But I can't remember how driving it was since it's been so long, so I'm not sure. How many transmission events should you feel? Doing a normal pretty casual and slow accelerating I'm feeling what I think is: 1 to 2 at 15ish mph, 2 to 3 at 28ish mph, then something that doesn't feel like the shifts do, it's subtler at like 32ish mph (which I assume is the torque converter locking in?), then 3 to 4 at 42ish mph. Is that correct?

Then cruising at 60mph it's running about 1850ish rpms. I can't remember what it used to cruise at 60 at.

Anyway, is the torque converter supposed to lock in right after 3rd gear? Should I feel another lock in after I get into 4?

Thanks in advance!
 

· Super Moderator
Joined
·
9,138 Posts
That shift pattern is correct. The converter locks shortly after the 2-3 shift. It doesn't unlock for the 3-4 shift, but it has a controlled amount of slip during the shift. The converter fully relocks during the shift and is undetectable.
 
1 - 16 of 16 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top