I have a 2002 Cummins with 5 speed transmission with an ongoing power loss issue under load. I have replaced the fuel pump system with and Airdog II system [preset to 17 psi] (no change) and replaced the VP44 injection pump ( more power empty) but still have an issue when pulling a loaded trailer. Sometimes it even loses power/speed going downhill. Can't get it to wind up. I KNOW it is capable of more because occassionally it will pick up power/speed going uphill in high gear. I actually have to let off on the throttle when I hit 75. Otherwise, it is pedal to the metal and constant shifting between 4th and 5th just to maintain 50-55 on level ground. I plan on increasing fuel pump pressure to see if it helps, but don't believe it will. Any suggestions?

 

if your truck is smoking bad during all of this id check the turbo and its wastegate actuator. and do you have any codes? good be a number of things causing this problem.

 

your fuel pressure is fine. try cleaning your map sensor.

 

No codes and no smoke that I am aware of. Been driving at night so hard to see. Getting ready to make another trip so I will watch closer. Thanks

 

is there a loose intercooler boot maybe?

 

sounds like your going in and out of limp mode. check the codes. i forgot to plug my map sensor back in when i took my programmer off and this is how it drove.

 

if you got a chip check the connections for it at the map sensor plug or it might be loose wire to your vp44

 

same problem here stock 99 with 6 tires vp44 was bad liftpump toast map and iat and crank and cam sensor replaced

still have same problem no power no leaks in my boots or intercooler i dn w =haTF is going in
i just keep dumping money

latest push on petal no go i think its time for the timbo apps

any one with the same problem let me know i am tired of it

little smoke when i start at a light is all i can tell you no codes except the apps low blah blah
HELP ME I AM 3000 in parts and still buying