Engine/Transmission (1998.5 - 2002) truck shudders or missing?

[smittybuilt]

i installed dd III's this weekend and i've noticed driving down the road if i'm not wide open the truck seems to shudder or have a miss feeling somewhere between 1800 and 2000 rpm's. i don't know if the truck is not completely warmed up running it with the big injectors or what. the temp gauge was somewhere in between 140 and 190. when the truck was warmed up to 190 it didn't seem as bad and wide open i could't tell it at all. any help would be appreciated. thanks!

 

[smittybuilt]

i forgot to mention that fuel pressure was o. k.

 

[mgoncalves]

Maybe some air trapped in the system still? I think if that's the case it will work it's way out.

 

[LSMITH]

I have done a couple injector swaps and I have never had one with any air in it after running for just a few minutes. I would doubt that is what it is. You could have a leak, and it could be internal to the head. I would definately get an oil analysis after about 1000 miles on it even if you cannot see any fuel contamination. It could also be a bad injector.



I would go out and warm it fully. Then loosen slightly 1 injector line at a time with it shut off. Start it and see if the problem gets worse or not. Do them all, loosen when it is off and DO NOT get close to the injection lines when it is running. It can and will inject you with fuel, possibly even killing you. If you find that one line does not affect the engine smoothness as much as the others then at least you know hle the problem is on. Then I would contact DD and see what they want to do. The above is going to make a pretty good mess on the engine and driveway. Some cardboard will take care of the driveway problem, and simple green will take the fuel right off the engine and any that may have gotten on the driveway too.



If you don't want to troubleshoot extensively on your own call DD and talk to them. They have enough injectors out there that odds are they know what your problem is.

 

[EShaw]

Does it happen when in OD/locked up????? Perhaps it's your brake switch that sends a signal to your TC and takes it out of lock up for a split second.

Eric

EDIT:

DUH... ... ... I read the wrong truck bio... ... you smiths are all alike ya know... ..... lol

I'm wondering if the old style brake switch might still be the culprit... .....

 

[Agades]

mine does the exact thing

stumbles when maintaining speed at between 50 to 60 mph

runs fine otherwise

it started after I had the dealer reflash for the high idle

the reflash did not work by the way

the dealer is going to give me a new computer

we'll see what happens next