foghorn

Thanks, Unless the VIN# gives away those secrets, I will rely on a good truck shop. Unless there is a way for this novice to determine early or late 91 and injectors non IC or IC?

bobva

My guess is you have a NON IC.

IC say intercooled on the valve cover plate.

NoN IC have a air tube that comes from the turbo over the head and into the intake manifold.
in this link http://www.pickuptrucks.com/html/history/segment12.html is a pic of a Non ic motor

j_martin

See, there ya go. My guess is you have an IC engine. IC engine, the air tube goes downward and to an InterCooler (IC) in front of the radiator. Then from the drivers side of said intercooler to the intake manifold. Nothing goes directly over the top of the engine.

The thing is, in addition to the addition of the intercooler mid 91, the electrical controls changed drastically.

bobva

You have the attention of the best truck shop right here.

Electrical stuff on theses trucks this forum knows more than any shop. you need to own one to know them.

j martin is one of best. plus many others. Im not one of them. I know my TollyCraft wiring.

patdaly

Guys, if he has Overdrive, it is an IC truck........ And he says his OD doesn't work.

Redtruck-VA

Good point...

foghorn

Thanks, if the VIN# gives up these secrets I'll let you know. Until then I'll try & find a diesel guy here to take a look to establish age and the injector status. Appreciate the feedback.

Hillbilly66

Mine is a late 91, I believe the door sticker has a manufacter date of 10/91, and it is IC truck. As has been posted easiest way is to look at your air horn as has been stated. If it loops over the engine and connects to the turbo, it is non IC, if it heads to the front of the truck, and you have a tube and rubber boot going thru the radiator support on both sides of the radiator with the tube on passenger side connecting to the turbo, then you are IC.

Injectors are different between the two, I believe it was the non IC had a larger injector than the IC.

The dealer should be able to tell you what you have with the VIN.

foghorn

All great info and I agree the best knowledge is found here on this forum. Unfortunately I'm on a week long trip for Thanksgiving and will not see my truck again until next week. With all this info I will not need a shop to figure the details. Hope I did not offend anyone, I'm new at this road diesel stuff. My old Massey Ferguson tractors don't relate. Thanks for the very professional assistance. Will advise findings next week.

bobva

Thats impossible

bobva

Patdaly you changed my guess from Non to a IC

I missed the OD in FH 1st post

foghorn

Great work guys, right on the mark, just looked at the cover "INTERCOOLED" and born 4/91 so she is an early 1991.Not sure what all this info leads to, so any suggestions where I should research now.

patdaly

Man, I went back and re-read your initial post. When you said lots of damage, perhaps did any of the fusible links on the duckbill get replaced? I would almost bet that it is one of 2 things, either you have no power thru one of the fusible links or your PCM is toast.

For grins, why did you replace the speed sensor? Was it obviously damaged, or was it the first attempt to fix the speedo/odo?

Next question, do you have a local source of another 1990-1993 cluster? It can be from a gasser, no difference.

I would strongly suggest you pick up a 1991 FSM on CD from Genos Garage, 35 bucks. I can post snippets to test, but to accurately diagnose things like the cruise, it would take pages and pages. I think if you find the problem with one, you will get them all back ( hopefully at least )

foghorn

Many thanks for comments and suggestions.
Speed Sensor replacement, one speed odometer shop (DNA) and an old dodge diesel local thought it could be the problem, not so! Wires or sensor did not have any apparent damage.
Fusible links on the driver fender well (Duckbill?) have several times been given the pull test, smell test, eyeball check, burnt check, and continuity test, seem to be okay. Other test suggestions? I don't readily have an instrument cluster, although that has been suggested before. All other instrument gauges work on present cluster, oil, tempt, fuel, volts.
I'll get the suggested CD, does DTR offer it? Seemingly the PCM will be very difficult to locate, any remanufacture or exchange vendors suggestions? Cheers and thanks a million!

patdaly

Ok, if you have voltage thru the fusible links and have checked every fuse, then lets look at the speed circuit.





As you can see, it doesn't go thru the PCM, so this is good news, if we get this fixed, then perhaps the rest will work.

I still haven't figured out where the power is coming in, I will have to look at it later.

Also, Genos for your manual.

http://www.genosgarage.com/1991-DODG.../#.VH8iUmer-rg