Rough idling and smoke

[mopar440cu]

I have an 01 Cummins and in the mornings down here in Florida when I start the truck up it idles rough and smokes for awhile. Any clues. Ive changed the cam sensor and filters. The fuel pressure guage says @ idle the truck has 17-18 psi. When i plug the motor in for the night and crank it the next morning the truck doesnt run rough, but without it , it runs rough??? I deleted the grid heater years ago but, this just started acting up. I dont think its because i dont have my grid heater in. Maybe the 110 BD injectors I put in the truck 4-5 years ago are clogged maybe?? how do you check them?? :ahhh:Got any clues?? Any info would be greatlly appreciatted!!!

[Mopar1973Man]

What the temp like down there? If the temp is above 32*F then there is no need for grid heaters... I don't even wait for the light on mine if the temp is above 32*F and normally pull my grid heater power leadf in the spring. i started as low as 25*F with grid heaters... Yes it will run rough for a second or two and smoke but clears up in a few seconds... Any error codes? How long till it straighten out? As for the injectors just take them to a shop and have them pop tested... The shop I went to the guys were great and took me to the back room and show me how they pop test them and what they look for.

[mopar440cu]

Its been in the 50's here, to us its freezing! No error codes. It takes alittle bit to straighten out . I dont feel any power loss though. If i had to take the injectors out and have them tested i would have to do some research on where to bring them, where i wouldnt get ripped off. Alot of shady people around here.

[Mopar1973Man]

50*F is not cold enough to require the grid heaters... Hmmm... Do you have a bad O-ring on the connector tubes? Air leaking back into the system and loosing prime?

[flman]

Its been in the 50's here, to us its freezing! No error codes. It takes alittle bit to straighten out . I dont feel any power loss though. If i had to take the injectors out and have them tested i would have to do some research on where to bring them, where i wouldnt get ripped off. Alot of shady people around here.

Pulling injectors sounds like a big 1st step. Start with simple things like air in the fuel as MM suggested. I think he is right on with the air in the fuel, because the roughness goes away. (Do you have a fuel pressure gauge? Uh Never mind ) Edited February 11, 2010 by flman

[Mopar1973Man]

Yea... More I keerp reading this the more i keep thinking its a air issue. Because the fact it only happens with cold starts. If a constant issues that never went away I would lean toward the injectors more... Chasing a air leak is rather tough at times... If its on the low pressure system you might pressurize the fuel tank and have some one look over the system for wet spots.If its on the high pressure side you might have to really look for damp spots, check connector o-ring, etc...

[mopar440cu]

Mopar how do I pressurize the fuel tank?? I dont visually see any leaks from the injectors on the head, nor anywhere else, that i can see. Also I read on your site i needed to adjust my valves@ 150k. Well I got to 01's with almost 290k on them and they never had them adjusted. Should I also adjust them, and what would it do for me after they are adjusted? Could the truck be giving me a fit do to injector fouling? Ive had these 110 injectors in the truck for 4-5 years. Can I clean them myself? Maybe soak them in Kerosene or something? Or do I have to tear them down. I figured if I do have to pull them again I will adjust the valves at the same time.:banghead:

[ISX]

The valves might be out of whack if they have never been adjusted. You might go through them and get them all squared away. Injectors should last a lot longer than 4-5 years and I really doubt yours are fouled. Being where the warmer weather is you really don't get cold enough to have the level of incomplete combustion that the freezing people encounter, therefore you shouldn't have much or as much, carbon buildup. The grid heater is debatable. There was a time when my truck would start at 0F without waiting for the grids and it wouldn't stutter or smoke at all, it started like it was 90F out. Doing this just for your enjoyment however, has negative effects. Right before I had the excuse of advanced timing, it would stutter at 0F using the grids.. The compression isn't what it used to be, and it smokes now. I am not sure at what temperature these negative effects start to happen. Might only be below freezing. Then again, the truck itself uses grids up til 60F. Maybe there is a reason for that. Nevertheless, I doubt this is your problem.

[mopar440cu]

LOL..We rednecks down here in Florida still freeze when the temps dip in the 50's:stuned:....I know its not that cold to you though..LOL:lmao: To get back to the truck.. thanks for your input ISX I appreciatte anybodys input!!! Sooo, you think maybe the valves Inever adjusted has something to do with the truck runnin rough?? Maybe mopar can give his advise also on the subject..

[Mopar1973Man]

As for pressurizing the fuel tank take a rag and blow gun and pack it in the filler neck. Give it a burst of air where you feel it leaking back out through the rag. (1-2 PSI at the most). This will pressure the suction system and allow for a second person looking for fresh leaking fuel that is wet at connectors, flex tubing and such. This will pressurize the system to the VP44 and the return line so check those too while your at it... Hmmm... Valve adjustment could be a issue... If you want to clean the injectors hook that truck to a trailer and find a steep hill and get the pyrometer up to about 1,000 to 1,100 and make her work for awhile. This will cook the tips clean. Being that all injectors are protected by the Edge filter inside the connector tubes... As for starting a Cummins without grid heater on a cold morning isn't a good thing in my mind... Like right now my grid heater are hooked up and I use then on the first start of the day if parked outside. After that I don't even bother... But once spring comes and I'm sure the <30*F weather is gone I disconnect mine and forget about them for the rest of the summer. Then in the fall I hook them up again... As for 0*F and colder weather I seen my truck nearly refuse to start on a single grid heater run... After two cycles it runs but still missing a beat or two for a few seconds... But thankfully enough this year we are seeing global warming (climate change)...

[flman]

The fuel pressure guage says @ idle the truck has 17-18 psi. When i plug the motor in for the night and crank it the next morning the truck doesnt run rough, but without it , it runs rough???

Just wondering, does your fuel gauge rise up for a split second when you first turn the engine to the run position, just before cranking it? If it does not do this, you definatley have a small leak, and the system has to re-prime itself. Also, if you can do this, try to park with the nose facing down hill, another good test of air in the fuel caused by leakage.

[mopar440cu]

Parking the truck with the nose facing down hill, will do what?...I would have to jack the truck up in the rear cuz theres NO hills in Florida where Im at, only swamps!!

[flman]

Facing it down hill keeps gravity fuel pressure on all the lines, no air can get into the system that way. It might even help show a leak in the return line? But so I have heard Florida is very flat.

[mopar440cu]

I faced the truck on our septic tank leech bed mound, nose down, and it still didnt start....Thisa is driving me nuts!!

[rburks]

I would just about bet that it is an injector issue...sounds like one is not completely sealing back shut. this will cause a very..small drip over-nite right down on the piston and when you start the engine the next morning all that excess fuel is on top of that piston and will cause smoke and rough idle until all of it is burnt off...& most of the time will not be noticable if at all driving after warm.... Have the injectors pop tested by a diesel shop..OK tell them what you are looking for that is " a drip overnite" tell him to pump up each injector twice, once to verfiy the pop-pressure and a second time to pump up to just right before the pop-off and hold it there for a few seconds.." if it drips theres your problem" Hope this will help Richie

[mopar440cu]

Thanks Richie

Edited March 10, 2010 by mopar440cu