Truck Cranks, but no start

[gsr46r]

Sup y'all,

New here, and I gotta dial truck 911. My 2000 Dodge 2500 Cummins cranks but doesn't start.

I scanned it and it said p0336 which is a bad cranshaft position sensor. I replaced it, cleared the code, tried to start the truck and got exact same problem.

I got a different CKP from advance auto. I also checked the wires for resistance and voltage. The middle negative wire in the hall effect sensor had high resistance, so I spliced in a new one and got a low resistance reading. I put everything back together and got the same problem- it cranks, but no start.


I need help coming up with ideas to troubleshoot and fix the problem. The batteries are good. The truck was running fine before hand. Only, the last time it ran, the tach said zero.


Here are the solutions I've thought of:
1. Replace Camshaft Position Sensor- I've read failure on this sensor can throw a Crankshaft Position Sensor code. Also symptoms for failure of the CPS are similar to CKP.

2. Replace wiring connector for CKP sensor

3. Pressure test lift pump to see if there's a fuel delivery problem

4. Take ECM to cummins to get scanned, reflashed or updated

5. Push truck off a cliff lol

Please let me know what you think. I also got the companion code p1693.

 

[Ozymandias]

Yes CPS and CKP work together, both are important for Injection timing. And he needs both for the start, as soon as it runs the CKP is enough.
CPS would be my first stop.

 

[gsr46r]

Thank you. I tested the CKP sensor, and it appears to work. I dropped of the ECM at cummins for them to look at. My next step is installing the CAM sensor. Hopefully, either the ECM or new Cam sensor fixes the problem! Will post once I try.

 

[JR]

I believe mid 2000 was the switch over for reading the Cam sensor vs the crank sensor. In other words, early 2000 and prior used the crank sensor for timing, mid 2000 and up was cam sensor. Do you know your trucks build date?

Do you have a programmer (tuner) in your truck?

 

[gsr46r]

Hi- No tuner in the truck. It's a late 2000- I believe the engine's made in december, 3 2000

 

[gsr46r]

Thank y'all- Good call on the cam sensor. It was tough to get to, but as soon as I replaced it, reinstalled the ECM, fuel filter housing, and starter it showed RPM while cranking. I killed the batteries from all the failed starts, so I connected it to my 2005 cummins and after gasping for fuel it fired up! Damn I was happy. This shows that a bad cam sensor can throw the bad crankshaft position sensor code!

I do have 2 post repair questions:

I got a leak coming from above the starter, maybe from a connection on the lift pump? Fuel drips down from above the starter onto the ground. Where do you think its coming from?


I noticed on the fuel filter housing's drain, there is no tube connected. I closed the drain plug and it doesn't seem to leak from there anymore, but I noticed a tube goes there on pictures of other trucks. Do I need to add a tube? Should the tube connect anywhere?


Lastly, is this a vacuum line? I accidentally disconnected this and have no idea where it goes.

(see 00:38)


Note: I did get this other leak fixed (seen earlier in the video) from the lift pump to injection pump. Do you happen to know what size hose it uses? I want to get a longer one for a better connection.

 

[Ozymandias]

No tube needed on the drain, thats just there to not splatter fuel all around while draining. Connects nowhere, ends above the pumpkin.

 

[Ozymandias]

The line could be vacuum to the cruise servo.
Im guessing on this as i have a gen3 with the servo below the driverside battery.

 

[JR]

Does look like a vacuum line. Is your HVAC stuck on defrost or does it change positions to the floor vents like it should? If it is stuck on defrost and doesn't change look for a tee missing a vacuum line at the firewall. The other end will connect down near the vacuum pump.

It's been a long time since I messed with the OEM sized fuel lines but I think it is 5/16. Make sure it's biodiesel rated hose.