I am a first time Dodge owner with a Cummins diesel. I have a 2001, 3500 with 5.9 Cummins, six speed. Truck has little power on take off and I have to wind out the gears. When I shift to 4th gear it will lug down some but when it reachs about 2200 to 2600 rpms you can feel the turbo kick in and it will take off. 5th gear is the same way but when I shift to 6th the rpms will drop below 2000 and the power falls off. It feels like I have a dead spot in the throttle when I press hard but if I back off some I will start to pick up slowly. But in 6th It will not get over about 62 mph. It gave me a code of throttle position sensor. I replaced it but no change, (luckily I knew the parts store owner and he took it and gave me my money back on it). I did find a vaccum leak and it started running a little better but still not like before. I would really appericate some help on this one, I am almost to point on giving up on it.

 

Welcome. First off, diesel engines dont use vacuum to regulate the fuel system, nor does the engine create vacuum because of the lack of intake throttle venturi. There is a vacuum pump mounted to the engine which supplies vacuum for the vacuum controlled accessories. If I remember right, the vacuum pump creates something like 22-25 psi vacuum all the time. When you have a severe enough vacuum leak, you will notice the vent controls stop working properly and default to the defrost selection and have excessive engine blowby.

If you have an APPS problem then you may still. You can always try resetting the APPS first before replacing too. Replacing with an OEM part is very expensive. You can get a Timbo APPS for a lot less and I understand that it can work better than OEM.

If you haven't had this truck for very long, or even driven a diesel before, then I can only guess that your idea of "lack of power" is accurate. I'm saying that because in stock form these trucks are no rocket but are capable of towing a lot of weight while maintaining great fuel mileage. Add some HP goodies and these trucks can easily become amazingly fast for their size.....but there's more to this if you want more HP. Here's a link with loads of information if you feel like spending time reading. http://www.dodgeram.org/support_pgs/diesel_ix.htm Might help you understand your truck better. And somewhere in there is a test for HP whereby listing how fast a stock truck should accelerate from speed to speed in what gear. That should help you know if your truck is lacking like you think it is.

Also, because you probably have no gauges, you have no idea what your fuel pressure is. The injection pump (VP44) on your truck is very sensitive to fuel pressures and too low of fuel pressure can cause low power and damage to the VP. In saying that, the OEM fuel pump is very unreliable and notorious for failing and causing the VP to fail. You might want to invest in a boost gauge, pyrometer for EGT's, and fuel pressure gauge, and a tranny temp if you have an auto.

Hope that helps you out.

 

Any other codes?

Any excessive smoke?

Checked air filter?

Fuel filter?

 

you might check the waste gate on the turbo..sounds like it might be stuck open..you should get boost long before 2600rpm..

do you have a boost gauge?
fuel pressure gauge?

-dkenny