my 93 d-350 is stock. I turned the smoke screw 2 turns.it is a 5-spd G-rag. when i first start it cold it has a miss and smokes. it did this even before i did the smoke screw. it feels like just one cylender is slow to get going. feeling the exhust it feels like the 4th from the front. after it is at opp.temp. it quits smoking. But dosent have a big ammount of power.Ive been running lucus and other diesel cleaners for a while. Could it be a bad inj. or pump going ?

 

Is there any kinda weird noises or anything?

 

Change Fuel filter first thing, Always start with that. If it knocks or sounds bad then loosen each injector line off the injectors one by one with the motor running. It should start to sputter and miss when its loosened and squirting fuel then tighten it back up and move to the next one with the engine still running. If you loosen one and it doesn't chang sound like the others or doesn't cause a miss then that could be the bad injector. I've heard of some people just swapping them to another spot and having it go away but if it were me I would get new ones or have the old ones tested. Also could be timing... how do you know that its cylinder #4?

 

That is actually cylinder number 6 if you go by the firing order.

 

Change the fuel filter, Pull the injectors and have them checked/replace them

 

thanks for the reply. When i first started the eng. i kept feeling the exh.manifold at each cyl.as it warmed. the forth from the front was slow to warm. .also it has a new fuel filter 3 mo. ago.

 

You could try swapping the #4 injector with another to see if the problem follows. That will help narrow it down.

 

Thanks Jim.Ill give that a try. But first Im gonna try a method that our local pump and injector place recomended. He said to pull and empty fuel filter then fill with a diesel approved varnish remover/cleaner.Let run approx. 30 sec.and turn off. let sit over nite.He said that after 150k. miles the pump and injectors will build up a varnish at the seats.

 

What fluid did he recommend?

 

Did you check the fuel pressure? The lift pump on my '93 went bad and would miss when first started and had no power because of zero fuel pressure.

 

you can buy "diesel kleen" in the grey bottle and get a new fuel filter, and pour the "diesel kleen" straight into the fuel filter, then run it for a little while, then let it sit overnight. the cleaner will soak into the injectors, then come out the next day and beat the ***** off it to clean the injectors out after the cleaner has been sitting in them all night.

 

thanks for yalls reply. It was diesel kleen. And i did let it set in engine after i let it run foe 30 sec. But the truck still runs rough when cold. It may be a little better. I may have to try it again.

 

CPesquire......don't know if this will work for you......I make a 700 mile trip every three months. This trip is on fast freeway, loaded with approximatly 900 lbs.....I use Howse injector cleaner - put two quarts in the fuel, and run her hard.....everything is up to temprature, and goes through multiple heat cycles. The truck just keeps running better and better......it sounds good, has more throttle response, and runs like it should......these 'square' Dodge trucks need something to work against.......good luck to you!