I have a 1993 Chevy 6.5 turbo diesel truck. I'm having a driving problem. It all starts at a stop and when I take off. The truck idles at about 1,000 rpms. So I take off pretty much normal until I hit 1500 rpms. At that point it likes to shoot from 1500 to 2000. It will hold 2000 for awhile till about 45 mph until it shifts back. My other problem is when I'm about 50 and more and I slow down back to idle speed the tach will jump from 1000 to 1500 almost making a chugging type action. I don't know what to do anymore and it's just getting annoying. I've changed a fuel filter, transmission filter and have bled the fuel system I just can't figure out what my problem is.

 

with the truck idleing does it die or spray fuel when you open the bleed on top of the fuel filter?

 

It sprays fuel out of the top bleeder on fuel filter and on the other bleeder valve and the fuel is always clean

 

not allot of other options really, if the engine is running improperly its a mechanical pump and all it needs from you is fuel pressure. Sounds like you have fuel pressure. If you can be sure its not a transmission issue i would be focusing in on the injection pump malfunctioning (broken governor spring, timing adjust piston/bore damaged, etc). Unfortunitly if it goes down that route it needs to come off and get replaced or rebuilt.

One other thing, might be worth testing is running b+ to the advance solenoid on the side of the pump and see if it smooths everything out, that would surely point to a failed injection put timing advance mechanism but it might get you by for a bit.

 

I'm trying to avoid an injection pump the best I can it's way out of my budget. Is there anything else I could look at I was thinking it might be a lift pump. Just can't afford an injection pump right now

 

i already had you test the lift pump, ops, and wiring by opening the filter while its running. if the pump or related parts were faulted fuel would not have came out and the engine would have died. What you can afford and what is wrong are very rarely the same thing. Spending money on stuff you dont need will only exaggerate the problem.

 

What would be the most inexpensive way to fix this. Are the pumps rebuildable? And how much am I looking at to rebuild it if possible. Would it be easier to find a reman one that is working properly. I can't see my self spending over $500 to fix it considering I only paid $1000

 

yes they are rebuildable. only thing is chances are the advance piston bore is damaged and if they dont have some good cores on hand you might run into some trouble. ebay some remans maybe, i havent had to replace mine yet so i havent looked. Just to clarify though i havent actually gotten to look at your truck so im just trying to assist you with the short description you gave me, but it sounds like a pump issue . have you tried powering up the advance piston solenoid?

 

Is the one your talking about on the top of the motor almost dead center it take a flat head screw driver to screw. I've played with it a little because the truck used to die so I turned the screw clock wise. When you turn it to the right the truck will idle higher when turned more to the right. Could this have something to do with it?

 

the electronic advance solenoid is on the passenger side of the pump near the bottom and back. should have a wire going to it from the temp switch in the coolant crossover. Not my picture, found it with a quick google search. This solenoid is -required- for cold engine operation. run like **** if it isnt hooked up or working. energizing it with a constant or keyed b+ might help stabalize your pump -IF- the failure is in the advance circuit.


To me this pic looks like its off a non turbo 6.5 or 6.2 but the pump is basically the same (diff settings and whatnot).