power loss

[acfloors]

I have a 2000 chevy express with a 6.5 turbo diesel engine. The problem is when I drive in the mountains sometime going up hill it has no power or when getting off the highway it has no power on the exit ramp also when getting on the highway it is very sluggish until it hits 70 then it acts like the trany shifts and it has good power. Any hints at the problem would be apreciated

[Bnave95]

I have a 2000 chevy express with a 6.5 turbo diesel engine. The problem is when I drive in the mountains sometime going up hill it has no power or when getting off the highway it has no power on the exit ramp also when getting on the highway it is very sluggish until it hits 70 then it acts like the trany shifts and it has good power. Any hints at the problem would be apreciated
Wonder if acfloors is still around? Hard to think he had no hits. Being a new guy,this would be disapointing even to me.
BTW,it's early in the morning,and I reading and looking back on what I may have missed:)

[Warren96]

Does it smoke when it losses power, or does it chugg like a cylinder is missing?

[Bornready6.5]

Lift pump comes into mind.........or filters....gotta start somewhere. If theres lotsa smoke, then maybe a vacuum problem or wastgate solenoid problem.

[acfloors]

no smoke just no power to accelerate until it finally gets up to about 70 to 75 and then it feels like the trany shifts and it takes off

[Mark Rinker]

Have you ruled out a plugged cat or exhaust restriction of some sort? Is it breathing freely?

Truck #2 (below) had this problem originally. No amount of troubleshooting on my part corrected it. Smooth, quiet, good starting, no smoke, but absolutely low on power when run side by side with #1. You couldn't make 70mph with a trailer and skidsteer in tow, and 0-60 times loaded were over 30 seconds. (NO JOKE!)

Unfortunately (?) it broke a crankshaft before the low power problem was corrected. With the used replacement motor came a new IP, and a list of performance mods that have made the truck a totally different machine!

In retrospect, I think there was a problem with the IP on #2. The amount of fuel being delivered to ALL cylinders was simply low.

Just a thought...

[acfloors]

most of the time it runs fine but once in a while it acts up. I think it may be a fuel issue because it acted up real bad when I filled up with conoco diesel out west it ran terrible then filled up with chevron diesel and it ran totaly different

[Bnave95]

How about fuel addatives,use any? Power Service is eazy to get. The gray bottle is best for warm temp but the white bottle is also good.

[Warren96]

The next time it acts up look in your mirrors and see if you can see smoke in your exhaust. Mine did that when it had a vacum hose leak to the turbo.

[atom_c]

I have seen some discussion in old posts about how much 6.5's smoke or don't smoke. Mine has never smoked much, unless I really lay into it with a load, then only a bit of smoke. Before I got gauges I was running for a while with no boost (I believe) because my vacuum line was cracked almost completely off. I did not notice any significant smoke during that time. My point is only that there seems to be some variability between trucks and smoke output.

[Warren96]

Born ready makes a good point. Air and fuel filters should be changed first,then a vacum gauge needs to be installed.

[Bnave95]

I have seen some discussion in old posts about how much 6.5's smoke or don't smoke. Mine has never smoked much, unless I really lay into it with a load, then only a bit of smoke. Before I got gauges I was running for a while with no boost (I believe) because my vacuum line was cracked almost completely off. I did not notice any significant smoke during that time. My point is only that there seems to be some variability between trucks and smoke output.
Let's look at your boost than. What are you seeing at any given RPM? Seeing how your running stock,the most you'll see is 7#. Once eng. RPM goes up the boost will not be much at all unless your pulling a load. The TQ converter should lock up in over drive around 45-50 MPH. When this happen's and the RPM drop and your into the power good the boost will come up. With the smoke issue,many 6.5 are not stock. Case in point,Mine;) I've seen many 6.5 stocker that don't smoke,ones that I do probley have turbo,wastegate issues or lack of filter changes. Close up a diesel air intake and it will smoke for the fuel is still being injected.
I can max 12psi and really smoke. Normal power on take off I won't see any smoke unless it's dark going around another car and there head lights will so I'm smoking,that's a diesel for ya:)