I just bought a 1998 2500 cummins. I bought it as is from a dealer. It had two dead batteries, and had been sitting for a few months. I got it going, and drove it home. I put two new batteries it it, and it ran great for a day. The next day, it was very hard to start. I could some times hear the lift pump running when i cycled the key, and other times i couldn't. when i finally got her started, my check engine light came on for a crank position sensor. could this be the problem with the intermittent lift pump? I also put in a different lift pump, which acts exactly the same as the one that was in it. It eventually starts, but after a lot of cranking and sputtering. once it starts it runs great. ANY HELP WOULD BE APPRECIATED, as this is my first diesel.

Thanks

Ron

 

I remember seeing quite a few posts about a crank sensor.. The Injector pump gets it timing from the position sensors so it could easily cause a hard start.. Thinking you have to take the starter loose to get to it? Cant remember really but it seems like I have seen that before

 

Yes the crank sensor is behind the starter on the block. Take the starter in to get it tested just to be safe since you will have it off.

 

If your engine isn't reading any engine speed it won't start or will be hard starting until engine speed is seen. It will just sit there and crank if no engine speed is seen and yes as stated above the crank sensor is located behind the starter.

 

thanks guys. this weekend i'm gonna pull the crank position sensor off and throw a new one on, because it seems like that is the problem. it will sit and crank, and crank and crank, then after a whilethe tach will register a few hundred rpms, then it will start. im also gonna put in a new fuel filter, as i pulled that out the other day and it seems pretty gunked up. ill let you know on my progress.
Ron

 

so i replaced the crank position sensor... what a pain in the tater tots. The plug broke off flush with the block, and I spent 4 hours trying to grab it with every tool available. I finally had to snake a drill in between the block and frame rail and drill a pilot hole for a decking screw. Then I attached a slide hammer, and mashed my thumb between the slide and frame. but after that, bang bang bang and it was out. Now it starts great, as long as it has more than 3/4s of a tank. ideas?

 

Scan for codes just to be sure. Install fuel pressure guage.

 

Do you have a aftermarket lift pump?