Engine/Transmission (1998.5 - 2002) Mystery wire, what's it do?

[340Mark]

Mystery wire? I just installed my rebuild but I can't find a home for this connector, all the others are pretty obvious. HELP!



Thanks... Mark

Sorry can't get the photo to go through

 

[Ncostello]

Maybe let us know the general area its in, what gauge, and maybe the wire color(s). Be glad to help you out if I can. Maybe my manual will give me some hints. Oh... what kind of connector does it have? Ring, plug or ??

 

[340Mark]

tried photo again no dice

I don't get it, it's justa small jpeg, must be me! Any way the wire breaks out of the harness crossing the firewall just on the drivers side of the valve cover then appears that it should come forward along the valve cover. It has a two pin connector ( two round barrels joined) wires are purple w black stripe and brown w green stripe. Hey maybe it never was hooked up?



https://www.turbodieselregister.com/forums/showthread.php?threadid=75500 Thanks

 

[Ncostello]

I saw your photo and the only thing I can think of are the MAP connector and IAT connector... both of which are right there on the head/block in that area. I dont see anything else in that area that requires a short harness like that. The lift pump and fuel filter heater and Water In Fuel connector (on the canister) are other possibilities although the plugs look different on mine (1999). Just a possibility.

 

[340Mark]

harness

Sorry for the confusion the wire is quite long, it would reach the radiator if it had too. I wanted the connector and the source in the same shot.

I did find a similar (and female)connector on the harness near the bottom of the timing cover near the vacuum pump and power steering pump, but it has a blank end in it like a weather proof cover.

Thanks

 

[Ncostello]

Careful there Mark... that wire does not plug into those two connectors down by the power steering pump.



The long one that begins where you have described goes down towards the transmission somewhere. Could be a speed sensor or something like that on the transmission. I havent crawled under there but I remember that one when looking. Cummins harness probably wouldn't have a wire harness begin at the back of the engine and go all the way to the front. The two empty plugs up near the front of the engine by the PS pump are unplugged on mine too. I think one has something to do with plugging in a computer for Cummins diagnostics. The other blank I cant remember. Be careful and make sure before you plug in. You dont wanna blow something.



Check down on the transmission real good first.



EDIT: Now I could be wrong but it looks like that long one on mine goes down to the top of my 5spd somewhere. Has to be a sensor there. I'm at work in good clothes so I cant go reaching up there to see exactly what it is but I did crawl under the truck to verify the general area it goes. You should be able to find it assuming you dont already have it plugged in and I'm wrong.

 

[Mundgyver]

The factory shop manual has a good section with all the connectors shown and what they are for. I would suggest looking there first for the type of connector and see what it tells you.

 

[340Mark]

Thanks to both Ncostello and Mundgyver. It never occurred to me to look at the trans. I just noticed tonight that the reverse lights are not working. I'll give it a look tomorrow. I have the Cummins book but not the Dodge book, time to shop!

Bye the way I just finished rebuilding this engine last week. I have a new respect for the Techs that work on these everyday. It's harder than it looks.

Mark

 

[Ncostello]

To heck with the reverse lights! Hows it running after your rebuild? Hopefully good.

 

[340Mark]

Just fired it for the first time 6/17/03 so far so good nice oil pressure, no smoke. I do have a check engine light on so I have to get the codes out. The vp44s condition is suspect and I need to have that tested. Also found the wastegate actuator has blown it's diaphragm. I don't have a way to read the codes right now. I would like to investigate the Palm pilot based reader and the laptop pc method. I saw your pictures with the lift pump replacement, that looks great!

Mark

 

[Ncostello]

How'd you know the wastegate actuator was blown?? Were you getting big boost numbers? That alone would probably set a code I think. Just curious.



I'm pleased with the lift pump setup. If my new pump is gonna last I'd bet it would have to be with this setup. If it dont then there is nothing you can do with a Carter pump as far as I'm concerned. It sure cost me so my new tires will have to wait a little while.

 

[340Mark]

I tested the wastegate with air pressure. Before the rebuild I was having a occasional low power or defueling situation, so I thought I'd check it. The truck would be going along just fine, light throttle on the expressway and the power would go down to about idle. I could push in the clutch for 5 sec. and then rev it and the power was back. I've read other post with similar problems that were more ECM or communication related.

The reason for the rebuild was that three cylinders had broken piston rings. I had just bought the truck a few thousand miles earlier, and don't really know it's history. My new motto will be don't ever buy a truck that had a fifth wheel.

I saw you had the bed off your truck was that just the best way to get access to the fuel system? A bout how much did the new system cost you.

mark

 

[Ncostello]

Taking the bed off takes me 1/2 hour. Unplug the lights, remove the bumper, take 6 easy-to-access bolts out, and have two more people help lift. Use loc-tite on the bed bolts. The service manual says they are "special" and must be replaced when putting the bed back on. Only thing special about them is blue loctite.



It seemed much more easier than trying to wrestle a 6' long tank thats still super heavy with 1/4 tank. Plus I couldn't make my hose connections until the tanks back in there... I could but it wouldn't be easy. I just like working with the tank were it rides.



My fuel system cost me around $550 but I spared no expense with quality twin Stanadyne filters. A simple pump relocation would be much, much cheaper... on the order of under $100 with ease. For $25 Practical Diesel Solutions Inc will make you a custom length pump wiring extender harness to you desired lentgh. They use the factory Duetsch connectors just like the cummins harness and also use 16ga wire which works just fine for the low amp pump draw (Carter).



Sticking with the stock filter is what most people will choose to do. It really cuts down on the cost unlike my situation. But I had other goals besides just moving the pump.