The Diesel Stop banner

1 - 10 of 10 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter #1
I'm having a problem with my 94 idi e4od. I have replaced speed sensor, mlps sensor and new plug, solenoid plug. It still sometimes goes to limp mode some times it clears itself and sometimes I have to shut truck off and restart. Code reader told me speed sensor was bad after replacing, replaced mlps and code said Fipl cleared codes the got speed sensor again cleared codes again git mlps out of range checked and readjusted it then codes went away. While backing a small trailer up a steep driveway the truck suddenly lost power and started overheating. Parked truck to cool off restarted it and drove home and truck acted like TC was staying locked up at idle stopped at light truck died restarted and it did it again. Tried backing into driveway and truck stated to die lose rpm's. Readjusted mlps again cleared codes while batteries were disconnected. Truck ran fine until I tried to back up again. Adjusted the shifter cable and shifter truck ran fine for a couple days. Driving home truck died turning a corner but restarted. it died 6 houses away from mine and would not crank. Ran a jumper to shut off solenoid and truck restarted and I got it home. Tried same thing next day and it wouldn't start , the wait to start light come on and went out very quickly and wouldn't come on again. Checked all fuses and the 2 fusible links on solenoid on fender noticed plug under power dist box almost unplugged replugged it. Bought a new ignition switch and Glow plug relay and controller truck started 7 times. Drove truck to bank and it restarted went to parts store to pick up new glow plugs and truck refused to even turn over and wait to start light quit working. Jumped solenoid on fender, truck cranked got it home. Not sure what to check next.:read:
 

·
Registered
Joined
·
3,553 Posts
This is almost mind boggling with all the parts your throwing at it without actually checking if there defective. Looks like your depending on the code reader to tell you the parts are defective.
WOT (Wide Open Throttle) Did you hold the throttle (Foot Pedel) all the way down while retreving codes? If not, reader will display false codes.

Tach Sensor. Is the Tach working smoothly, showing the correct RPM?

VSS (Variable Speed Sensor) Did the speedometer actually quit working?

MLPS (Manual Lever Position Sensor) Does the truck up shift properly? 1-2-3-OD? With the shift lever in Neutral, did you line up the Neutral marks on the MLPS?

GPC (Glow Plug Controller) It's normal that the controller will not cycle if the engine is hot, or the ambient temp is 80*F-90*F, WTS (Wait To Start) might come on for just a second.

Jumpering the IP FSS (Injector Pump Fuel Supply Solenoid) Having to jumper that and not being able to crank, says you lost all power to the key switch. Without checking where you lost voltage, no one can tell you what your problem is. All 12VDC comes from the connections at the starter relay mounted on the passenger fender, it goes to the key switch and branches off to the fuse panel. A VOM would be your best friend.
 

·
Registered
Joined
·
5 Posts
Discussion Starter #3 (Edited)
Yes WOT when checking codes. Transmission usually shifts right. I get an occasional Limp mode but not often. Rechecked codes says there are no problems to be found now. I installed new Gp controller because mine would click sometimes but not like it did when it was new. Also went ahead and installed new GP's ZD9's. Tried starting truck to get air out of inj lines and nothing. Jumped solenoid and it turned over. Bought new solenoid and same thing everything lights up as it should. but no turning over. Wiggled shift lever and it cranked. Unless I either do not have mlps adjusted correctly,(Shifter in neutral line up the lines) is how I've done it. Even tried hanging weight on shifter and adjusting linkage. I didn't move the shifter when I installed the new ignition switch at lower steering column, unless it may have moved on it's own, it went in with no problem. Could be a bad mlps, it's a BWD 1 year old now. or a short which I can't fathom because moving shifter down and back into park and it cranks. Also fuel shut off is now clicking again when is on. Could the solenoid on the starter be bad? I tend to believe either mlps is not right but done as the book says, or shifter linkage , or ignition switch is some how out of adjustment. But open to all suggestions. Wiring is not my strong point. Yes tach and speedo work.
 

·
Registered
Joined
·
3,553 Posts
This key switch installation is for an 89, but should be the same for your 94 IIRC.
 

·
Registered
Joined
·
5 Posts
Discussion Starter #5
Gremlins

Thanks for the diagram I will try this, but the truck started doing the no start until moving shifter before I replaced anything or done anything. I'm still leaning toward the mlps after crawling under truck I finally had someone to help by turning key as I loosened the mlps and moved it back and forth. Still no start. unless moving shifter. The only other thing is there something inside trans to do with the pawl for park? Every thing on truck is original except 3 fuses. 1 tailight
bulb. and both headlights, 2nd transmission, injector pump, alt, water pump,abs module, throttle position sensor, speed sensor,starter,vacuum pump, brake booster and cylinder, just replaced all injectors and gp's. Not bad for 21 yr old truck w/297,000 miles on her. :thumbsup:
 

·
Registered
Joined
·
2,374 Posts
You can confirm your suspicion with a simple test - identify the two terminals on the MLPS connector that are for the starting circuit, and jumper them with a wire. If it starts, then the rest of the circuit is good, and it's the MLPS, either still not adjusted right, or just inop.
 

·
Registered
Joined
·
14 Posts
I Want to thank all you guys for all the great advice. I have been trolling this site for over a year now. I've read nearly every thread on the e4od.
I Bought a 93 f350 crew cab 7.3 IDI. Odometer reads 74k looks great motor is strong but that?$&!? e4od.
I Knew the previous owner who had it rebuilt few miles ago but he let every gandy he knew drive it and work on it.
Here is my problem, under steady acceleration it shifts through all the gears and into od when I let off at 70mph or so it shifts back to third. It stays there till I romp on it then it shifts up to od.
So you know I've done all you have suggested just ran test on tps good reading all things outside of pan check out fine. Please help me I've become willing.
Sorry coudn't figure out how to start a new thread so I just tagged onto one
 

·
Registered
Joined
·
5 Posts
Discussion Starter #8
Ok after trying everyone's suggestion and replacing everything but the TPS (which is the 2nd one the truck has had and at 298000 might be time for another one. It turned out I found one other thing by accident, went to dr appt at the VA and came out and truck wouldn't do anything as far as cranking goes. Lights worked, radio worked, couldn't crank with key or jumping solenoid. My friend came to help me and removed the wires off solenoid and asked did I put these on right and I said just like they came off the old one. As he was putting them back on the pulled on the 6 or 8 gauge wire on the post that goes to solenoid and it came out of the fairly new factory style battery cables. It was corroded. So we temporarily tightened between where the clamp tightens up and she cranked. The cable is only 3 years old and I hate to toss another $80 backs out for another one. I tried the big repair post on the old one it worked but it didn't fit very well. I wonder can I clean out the old hole and restuff it back in and solder or epoxy it back in somehow? I did but a crimp on lug to bolt it to the terminal, and I bought a stainless steel allen screw that I thought maybe I could drill and tap teriminal and tightned it down that way if sloder or epoxy is not an option. Any other suggestions? Also is there a ground wire on the transmission that grounds to the body? The tranny still wants to shift in limp mode every once in a while. I'm thinking if it ain't the TPS then it has to be a ground some where.
 

·
Registered
Joined
·
1,838 Posts

·
Registered
Joined
·
1,651 Posts
Peel the insulation back a good ways, put some shrink tubing over the cable, then heat and solder a new terminal in place. Run the shrink tubing up and warm it up so it shrinks over the exposed wire, and terminal. Don't use epoxy, it is an insulator, and I don't believe any set screw will hold any more than temporary. About your ground question, yes a poor ground will make you pull your hair out, check them all.

You can check your TPS with a good ohm meter. All it is is a potentiometer. If you hold the ohm meter leads on the terminals with power disconnected, then tun it through its travel you will see the reading change accordingly. I you see a flat spot or a big jump in the reading, then it probably isn't any good.
 
1 - 10 of 10 Posts
Top