went and started it up at work to go to lunch and i hear a tick. and that tick is caused by a misfire or a miss. since i can hear a puffing out the exhaust really loud at idle. the miss is there through the whole rpm range and egt's are higher than normal(cant get under 400*F at idle no matter how long it idles) so did an injector crap on me now? or what, please dont tell me its the ip now
When my injector failed i noticed a slight miss under load (with tc locked) I also had bellowing white smoke coming from one cylinder. (turned out to be number 1)
this is horrible though. at idle theres a really really loud popping coming from the exhaust, not like a gas engine miss where its a slight pop but a real loud TUFF TUFF TUFF sound. and if you free rev it up it shakes the hell out ofthe truck then revs up to 3200 rpm and its smooth up there. and i had my head out the window while going down the driveway while accelerating it was shaking really bad and smoking a fair bit then every once in a while id hear a loud pop from the exhaust like that one cylinder was trying to fire and there was raw fuel in it.
hopefully its only injectors because i can get 6 new ones for 300 bucks, theyre stock but ill live with that since these stockers worked pretty well. im almost wondering if i burned a valve on the way home because it wasnt this loud before.
knowing my luck, probably have a melted piston now since it wasnt making this terrible sound in town where i parked it but by the time i got home she was really making a racket. it goes away at higher RPMS though so i was hoping it was an injector. i never thought to pull the oil filler to check for puffing.
i just got it home and its dark and i dont own a cummins compression tester. ill see if my boss has one but i doubt he does. how much do they run? he told me to pull off the exhaust manifold, block the turbo feed line, and start it to see which runner is puffing and to see if its blowing fuel out.
I'd definately do the compression test but, the popping sound would lead me to believe it's a burn't or misadjusted valve. I'd check the valve lash as well. Good luck, Dave.
if i dont find anything wrong with the #4 injector ill be rigging up someway to presurize the cylinders with my air compressor and run a leakdown test to see what is leaking(intake, exhaust or rings/piston itself).
its the #6 and/or #5 cylinder since #6 has no difference in engine operation when the injection nut is loosened. #5 has a little difference but not much, all other 4 cylinders when loosened the engine will rock around a ton then die so theyre all working. i removed the intake elbow and grid heater and fired it up, terriblly loud snapping/puffing sound in the intake manifold and when i shine a light down in the hole i can see while smoke blowing around in there a bit. then when i shut it off the white smoke rolls out from rearward somewhere. i removed the #6 valve cover(what a crappy design on dodges behalf on how to weasle that out of there) and found both valves to be operating and neither have excessive lash in comparison to the other cylinders. so now im thinking somehow my intake valve for #6 is burned or chipped or a chunk of carbon is stuck under it. theres no excessive blowby and no "puffing " from the oil filler so my bottom end is alright, so im assuming i need headwork. if i had to change the #6 valves would i get away with only lapping them in or do i need to have major machine work done to the head to make them seat good? thanks for all your help guys, i only bought this dodge to get the cummins engine because ive heard nothing but good about them but since ive bought it ive had issues upon issues with the engine and front axle. also how much does a reman head cost? and would it be a cracked head causing this?
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