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Need help... Hopefully you all can help me out never owned a deisle before. I have a 1998 Dodge Ram 3500 12v turbo power. This used to be a tow truck and the previous owner converted it to a daily driver. I have to jump start it every time you want to start it. Once the truck is to the starting position and cranks over which starts up fine. As soon as we release the key the truck dies. Replaced the entire ignition thinking that one of the pens off one of the recalls I saw on the form was the problem. This didn't fix the issue. Please help.
 

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Something FSS-related is indeed the very likely culprit. Zip-tying or wiring it up as ekvhekvh suggests will confirm that. It may not itself be bad. Check fuses 2 and 3 in the PDC and fuse 9 (Engine) in the fuse box. The FSS relay is likely good since the FSS must be coming up when the key is at 'start'.

Note that with the FSS tied up, the motor will not turn off even when you take the key out (This is, in fact, the purpose of the FSS), so have some wire cutters handy :)

Why must it be jump-started? Are the batteries dead simply because it hasn't run in a while?
 

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Thank you ekvhekvh for the diagrams. I have never even worked on a diesel until today when my ignition lock switch and the starting switch came in from RockAuto. My brother-in-law said it was the ignition he is a mechanic. Went to our truck that's broke down and destroyed the whole assembly, because he wanted is to buy the truck from us. I got this in a construction job trade for $3500 with only 200,000 miles on it. Anyways I got the old switch out and replaced today. I'm very blue print and mechanically inclined. I work for the DOD aviation building inspection. I looked dup the issue before he said he would fix it. So I had some idea of what could be the issue and there were several things so I looked up what the Parks look like but I wasn't sure where they went to on the truck because I couldn't pull up very clear diagrams off the internet. Is the number 9 fuse in the fuse box control inside the cab? Or do you know I appreciate the help I am going to try this in the morning.
 

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Thank you jimduchek, I did switch out some of the fuses and relays for the systems that I knew worked already. All fuses are in good condition they're very snug and they have not broken and they do not have corrosion on them or have burnt ends to where they look like they have malfunctioned at the PDC. I do have a interesting homemade wire that I did not apply that goes over towards the fuel relay and it's got a 15 micro amp fuse in it that is very corroded so is the inside of it it's something homemade that was put on the truck before I got there I did try to clean the terminals but there's a lot of corrosion I plan on replacing that fuse it looks like they may have tried to bypass the number 9th use cuz everything that I've seen on the number nine he was being a problem from 94 to 2001 diesel trucks for Dodge show a certain connection in that area for like see 125 and 126 I think it is. And before we got the truck in the construction trade it headset since I'm going to say July of last year before it was started again we ran all the way home with no issues and ran a few errands but later that night it shut off after we had to extremely down shift the truck no blinker turn and the awesome completely stop on a dime from the car in front on me. Right after this immediate ship down and slam on the brakes the car went down the road for a little while about another mile mile and a half and then all of a sudden died. The same thing as I stated before right after this turn over the vehicle starts no problem as long as you leave it in the cranking position as soon as you put it to the run position dies. Thank you for your help with all of this I can't wait to get back to my beast and try all of theses suggestions.
 

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Update. So the Casino called today and asked for us to move our truck. Thank you jimduchek, and ekvhekvh for the advice. I took a coat hanger and hooked it around what appears to be a bass adjustment thread bolt and hooked it to a hard line fuel nut. Started right up but oil, tack, speed odometer didn't show any thing. I know the sensor is brand new no sign of grease, oil break down, so with the problem that I had the fact that we had to downshift suddenly and stop on a dime almost going into the ditch is it possible that one of the adjustments or brackets fell out of this?
 

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I just recently replaced my FSS and dug into the setup while I was at it. There are actually two separate circuits, one that operates at high power when the ignition is in the START position and a second lower-power circuit that is active when the ignition switch is in the RUN position. The first higher power circuit is responsible for actually pulling the solenoid in (moving the lever on the pump), allowing fuel to flow. The second lower-power circuit is only responsible for holding the solenoid in that position while the ignition is still on. With no power to either circuit (normally when ignition is OFF) the solenoid will move back to the fuel shutoff position, probably via an internal spring. So your issue could be that the first higher-power circuit is working correctly but the second lower-power circuit is not getting power. In that case it would start but immediately shut off when the ignition is put back into the RUN position.

Another possibility is that the FSS linkage to the pump lever is not set correctly, i.e. it's too short. It's important to remember that the second lower-power circuit that holds the FSS in the fuel-flowing position will only work if the solenoid itself is in the right location, i.e. fully pulled-in. If the linkage is too short the lever on the pump will hit its final position before the solenoid is fully pulled-in and as a result the second lower-power circuit will not be able to hold the solenoid in the fuel-flowing position. Check out the SOLENOID SHAFT ADJUSTMENT part of the service manual that was posted above. I would put money on this being the issue!
 

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Started right up but oil, tack, speed odometer didn't show any thing.
Do your turn signals work? Starting to suspect fuse #3 in the PDC, or something around there. The 'start' coil in the FSS powers thru fuse 2, but the 'run' coil powers through fuse #3, along with most of the dash. And the turn signal flasher. Even if the fuse is good, stick a voltmeter probe down in there and make sure it's actually even getting power.
 

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Do your turn signals work? Starting to suspect fuse #3 in the PDC, or something around there. The 'start' coil in the FSS powers thru fuse 2, but the 'run' coil powers through fuse #3, along with most of the dash. And the turn signal flasher. Even if the fuse is good, stick a voltmeter probe down in there and make sure it's actually even getting power.
I didn't know that much of the dash runs through the same fuse as the FSS hold circuit - nice! Starting to make sense.
 

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jimduchek yes the turn signals worked and the fuel gauge worked on the control panel the temperature gauge and the voltage battery meter ran as well.and the person following the truck scene at the turn signals did work and the brake lights as well. But getting no power to that number 3 fuse would make sense because the fuse is not blown. tomorrow I plan on posting some pictures of some things that were added to wires the see if you guys can help me figure this out and get some diagrams there's a lot of harnesses I noticed when I was up there messing with the FSS that are not connected to the truck I'm not sure what modifications he did this being my first diesel ever.thank you all for the help and keep the suggestions, because so far it's starting to see some light at the end of the tunnel.
 

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jimduchek yes the turn signals worked and the fuel gauge worked on the control panel the temperature gauge and the voltage battery meter ran as well.and the person following the truck scene at the turn signals did work and the brake lights as well. But getting no power to that number 3 fuse would make sense because the fuse is not blown. tomorrow I plan on posting some pictures of some things that were added to wires the see if you guys can help me figure this out and get some diagrams there's a lot of harnesses I noticed when I was up there messing with the FSS that are not connected to the truck I'm not sure what modifications he did this being my first diesel ever.thank you all for the help and keep the suggestions, because so far it's starting to see some light at the end of the tunnel.
I just realized you've got a 98, not a 94-97. So a great deal of the dash stuff I'm thinking of may be wrong. Let me dig up some 98 wiring diagrams and see if anything interesting pops out.
 

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I looked up some diagrams and some videos on the relay switch for the FSS and it appears that my relay doesn't look like any that I've seen before most of them are four prong this one looks like it's an eight. I think it might be a 60 amp. And the owner before me created a bridge to the green and black wire that crosses into the dash to that harness relay assembly with a 15 amp fuse just to the green and black striped wire very odd. And a previous owner didn't think it would run at all. I did some checking today during the daylight and the Carter PIN is not in the FSS which makes me think that it's possibly not adjusted to the correct height
 

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The year is 1997. I just got the title back.
Ah, good to know. It's odd that you're seeing coolant temp but not oil pressure -- those two are virtually identical in how they are powered and how they work. There's really nothing (other than one of the actual sensors or gauges failing) that would make one work and not the other. The sensors DO fail though. Was the oil pressure gauge working before? I know this truck is new to you... We may be looking at several unrelated 'preexisting conditions' that are making diagnosis more difficult.

As far as the FSS relay goes, that's only used to power the 'start' coil in the FSS, which apparently is working for you. The 'run' coil is directly powered through the ignition switch. As far as the FSS height goes, I would be surprised if it's not adjusted correctly since you can get the truck to start, combined with the dash issues, but I could be wrong.

See below on the FSS connector. Would suggest pulling it off, putting the key in 'run' and checking between pins A and C with a voltmeter. If you're getting voltage there, then perhaps all your dash issues are a totally separate thing. If you are not, check voltage between pin A and the chassis and check continuity between pin C and the ground. i.e. you might be getting 12V to pin A but the ground is somehow disconnected. We can work backwards then through the system and find where the disconnect is.

If you ARE getting voltage there, then I'd be thinking the FSS itself has failed and only the start coil is working.
 

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I had the same problem when I replaced fuel shutoff. I had to adjust the rod and it worked perfect.
 

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Ok so the FSS will not stay in the up position after I adjusted the lever, but just looking around I have several connecters disconnected see attachments. I also took a picture of the strange fuse able link that was added from the last owner.
The fuel filter wire harness is not connected and another wire harness on the same wire section.
 

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Ok so the FSS will not stay in the up position after I adjusted the lever, but just looking around I have several connecters disconnected see attachments. I also took a picture of the strange fuse able link that was added from the last owner.
The fuel filter wire harness is not connected and another wire harness on the same wire section.
Doesn't look like the attachments worked. That happens sometimes on here :( I can't recall, is your truck an auto or manual?
 

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If anyone has a full 1997 5.9 liter 12 valve turbo diagrams for the fuel filter harness wire cluster I think it could help me out with why the two wire harness's are not connected.
 

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The connectors around there are the water-in-fuel sensor, which is on the filter canister/module itself, and the fuel preheater which is in the fuel prefilter mounted behind the lift pump. Deleting the fuel heater is a fairly popular mod... it's kind of a leak source and doesn't really do much, so that could be one. The oil pressure sensor is in the block not too far from there either... don't think offhand it comes out of the same harness, but I mention it just cause I know you said your oil pressure gauge wasn't working. Up around the FSS there ought to be a connector hanging off for the throttle position sensor, which isn't there on manuals.
 

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