I am new to the site as well as diesels. I have searched around but dont have internet at home and dont have enough time at work to search for more than a minute so sorry if this is a repeat question. Recently when I start it in the morning It will run like crap. Their isn't the loud clatter that usually comes with a diesel the motor runs quiet. It also blows a lot of smoke if I get on it. if i let it warm up for a while and then drive it will do it but will "clean out" after a couple seconds. It does it even during the day. Yesterday leaving work it was 70 out side and the truck had only been sitting for 5 or 6 hours. Any ideas or suggestions would be greatly appreciated. Oh 93 3/4 ton auto w/overdrive 160,000 miles.

 

One question comes to mind off the top.
Is it a work or personal vehicle? I mean does it see severe use or just personal transportation?

It's really a loaded question because there can be quite a few possibilities.
How was it maintained? Has anyone done any pump mods? Is it used for hard everyday work?
The most probable cause would be that the engine is getting tired and worn.. Worn valve guides and stems and seals will cause that almost 75% of the time, but chances are when they're worn out to that point, so are other things.

It's definitely an engine problem and wouldn't be solved by some easy fix.

 

whatever it is it just started about a week ago. One day it was fine the other it was like that. I have only owned the truck for a month or so. It is only used for transportation. I believe the pump has been played with.

 

Just my 2 cents but you might check you fuel filter. I drained mine because it was white smokin in the mornin.

 

I would also check your KSB selenoid (sp??). If that is not working properly, it will smoke upon first start because it is not advancing the timing just right. Once warmed, good to go. Does sound strange though as you stated it was warm outside.

 

I drained filter, no water. Just went to lunch got in started truck and it misses and sputters when i get on it. If it is just idling or I just "bump" the throttle is sounds. But if hold it for a moment it dogs out. Could it be one of teh injecters not working properly until it gets good and warm. Just a thought.

 

Could be an injector or even the Manual feed Pump. Maybe the fuel is draining back into the tank instead of staying up on pressure. You can unscrew each injector just a little (watch out, high pressure, protect your eyes) while the motor is running and it should die down or run faulty. If it doesn't change, then that would be a bad injector. If it does change, then tighten back up and move to the next one. I should say not so much as unscrewing the injector but more the fuel line attached to it.

 

It does sound like an air leak to me, too.

 

An air leak at the injecter?

 

Probably. Either that or at the back of the pump. If it was getting air before the pump it would be difficult/impossible to start and would run like crap all the time if it ran at all.

 

I had two injector lines leaking at the back of the pump and it ran fine just leaked fuel.

Weird oh

1. Change the fuel filter (use the good stuff) regardless of the history.
2. Change or verify that your supply fuel pump is working. I would change it. Its cheaper than tearing down the engine to troubleshoot.
3. Check injectors by cracking lines.
4. Check air filter and intake in the turbine. Spin turbine wheel, it must smooth and free, no play.
5. Check AFC tube, it controls the fuel and works off of boost.
6. Let a DIESEL mechanic inspect and troubleshoot.

I hope this helps and is accurate.

 

I'm going to throw my hat in with the guys who suggest a fuel system problem.

First thing I'd do is run a good double or triple dose of fuel conditioner thru the system. Don't worry about "using too much". You won't do any damage and you are trying to see if an additive will help clean up the fuel pump internals, injector lines, and injector tips. Usually using 2 or 3X recommended amount will produce a result fairly soon.

Do you see any signs of leakage from the injectors/lines, injector pump and/or surrounding area, or the lift pump area???


You may have an injector that is sticking or releasing too soon (that needs to have the injectors pulled out to check for confirmation;

You may have a loose injector line, at either end;

The AFC boost tube is not a likely culprit here..;

Your lift pump may be on it's way out as noted, the normal pressure on that is about 8psi at idle and as low as 3psi at wide open throttle (WOT). If it drops below that you have a lift pump problem just for starters and it may be contributing to your problem but not the sole cause of it;

Check all the connections on the fuel lines, from the tank side of the lift pump to the injection pump itself, although that is not likely the source since they rarely just "loosen off for no reason" over the course of a week or two, but worth checking;

What color is the smoke?? Black? White? Grey? Blue?... warm or cold?

The fuel solenoid may be starting to fail on you. You can find it on the back/top of the pump just above the injector lines. It has two wires attached to it, a black and a blue. Pull the wires (don't matter which one goes on which spade connector), remove the solenoid (it's a bit tough to get at) taking care to get the internal spring and rubber tipped metal plunger out, then look down inside and/or use a small mechanics magnet to try and "fish" for any metal shavings. If you find any, your pump is pooched. Since the solenoid is out, inspect the rubber tip for any sign of chipped rubber edge.

Check the fuel tank for vacuum. It should not have any....;

Go from there and let us know how you make out...

pastor bob....Our Lady Of Acceleration Church

 

the smoke is blue until i "clean" it out then it doesn't hardly smoke at all. This is only if it sits for a period of 2 or more hours.

 

blue smoke is an indicator of burning oil. not fuel or antifreeze.
I still say it sounds like valve guides or seals.
But what do I know? I'm only an auto and truck mechanic.

 

I'm sure it's oil, mine does it too. Just the nature of the beast. You'll get blue at start up for a bit, then when you get going and get the driving pressures up it goes away. All the diesel tracks and trucks I was on in the service did it. Even if you go through a quart of oil between changes, it's cheaper than a valve job. you describe your vehicle (including mileage) in your signature, it would help with the answers.