When my truck warms up and I get on it pulling out on the highway my engine seems to overload with fuel. It blows black smoke real bad and has no power. Any ideas?

 

inop turbo, no boost... most likely..

 

Don't think so but I'm not a diesel mech. I can hear my turbo. So I assume that means it is working. I am also having problems with it bucking going down hill. I was thinking vacumm but as I said I am not a diesel mechanic.

 

What codes are you getting ? I am willing to be there are at least a couple in there having them codes may help us better to help you.

 

No code's

 

Be sure your "scan tool" is compatable with, set up for and working properly.
Some cheaper scan tools have issues communicating with GM diesel (OBD1 &2)applications..

I suspect your limping it but should have DTC(s) present....
No codes present, suspect fuel delivery issue- fuel starvation,, fuel restriction, air infiltration, lp cavitating due to clogged fuel strainer (dirty sock), inop/faulty LP (faulty OPS), most likely..

Air bubbles (something) are likely disrupting the Optical Sensors day at the diesel spa and in turn the PCM is cutting boost and reducing fuel thus producing the heavy black smoke and poor performance under heavy acceleration.


*Could also be a break down within the boost system.. A thorough underhood visial and physical inspection will often find and resolve most driveability issues.. VP should produce 20" minimum, should have 15" minimum at the WGA with engine idling.. all im sayin..

 

Scanner is TP-270CAN OBDII. looks like it has new lift pump. Going to try and drop tank today. But believe its temp related because when engine is cold 150 or lower it runs like a top.

 

Below 150 degrees, the PCM is likely still operating in Start Up (Cold Engine) Mode.
During start up mode, fuel delivery is increased and timing is advanced slightly.

Experiment- With engine up to temp, disconnect the ECT sensor (cross-over) and see if the performance drops once the gage indicates its up to normal operating temp.. This tricks the PCM into thinking the engine is cold.. If performance doesnt fall off at operating temp, your ECT sensor may be skewed and the PCM thinks its overheating when it reaches normal operating temp...

With a scan tool, you should be able to compare the I/P gage reading with the PCM temp reading, they should be fairly close....

 

No change in performance with ECT sensor unplugged, it just idled higher.

 

You mentioned vacuum, good start, Simple test, start engine, let idle and remove the black plastic vacuum tube attached to wastegate on turbo and check for vacuum in black hose. You have a vacuum pump solely to control wastegate and EGR valve if CARB truck. The black tube is formed with all kinds of bends and goes to a solenoid valve on drivers side valve cover at rear of engine. The other tube on that solenoid is orange. It goes with same bends around intake manifold but goes to vacuum pump. These tubes crack and break ALL the time from heat & age. Sometimes the vacuum pump fails but it makes noise or locks up and burns the belt off. If you have vacuum present, remove and attach repeatedly and watch wastegate rod going to back of turbo for movement. If no movement, wastegate is bad(rare, but sh** happens)! You will always hear the turbo whether wastegate is working or not. Stupid vacuum system to control boost, Ford used a similar set up on Super Duty 7.3s.