drove my 01 cummins to work yesterday ,everything fine, got in to come home, started but ran very rough and no throttle response. shut it off and tried again no start. replace lift pump, starts but only a really rough idle and still no throttle response, code PO 252, any help would be appreciated. it is all stock no mods except 4" exhaust and only 91000 miles . Pretty sure I got all the air out

 

Normally a bad Cam sensor is a different code than this. The code P0252 is usually a bad thing, but you could check your cam sensor wiring just to be sure.

dtc-code-p0252.pdf

Check your camshaft position sensor. Check the plug for damage.
check- should be a three wire plug Vio/Wht wire is 5 volt supply, Blk/Dkblu is the sensor ground, Gray sensor signal.
The ECM receives the crank signal input from the camshaft position sensor.
Note in 2001 dodge changed from using a crank sensor to a cam sensor for relative IP timing.

Also check your wiring to the VP44 injection pump if all that checks out you may have a failed VP from fuel starvation or a bad ECM.

 

thanks Jet fuel, will try it this morning, also do you know where I could get ring and pinion for this truck? it has 4:10's in it and I don't pull anything anymore would like maybe a 3:30 to 3:50 range

 

There is a 3.55 gear set in some of the 3500 and 2500 trucks/vans. probably wouldn't be hard to find.
You could try and advertise in this section what you are looking for.
Wanted To Buy (WTB) - Used - Diesel Bombers

 

like jet a fuel says checking cam sensor on 01 might be worth checking out. most of the time it thats the problem your tach will be crazy jumping or not working at all.

 

Ok replaced cam sensor, truck starts but only idles and rough, no throttle response.still showing same code p 0252. Im thinking TPS ??only sthing left before pump. Im thinking if it was the pump it would not run at all..Am I correct

 

after reading other posts and looking up codes for dodge found that P0252 is a fuel valve stuck. pinched off the return line, truck runs perfect. next question , where is the return check valve? took the check valve off at the banjo fitting on the vp it appears to be working. truck runs with vice grips on return line, will not run with out them any ideas?

 

You must have a bad lift pump or a bunch of air still in the system. Need to check your lift pump pressure.




here is the return line and the overflow valve is in the banjo fitting.

 

have 12 lbs with truck running and fuel return line pinched off, 0 showing when return line open, new lift pump bad or return check valve? 12 lbs when truck off and pump running

 

I would try a new check valve the release pressure according to the chart is 14 PSI. Sounds like its not holding any pressure maybe the spring failed or possibly the banjo bolt is the wrong one.