white/grey smoke after towing 12000lbs

Rerywilson277

2002 LB7
Nov 7, 2013
25
0
0
Havre de Grace, Maryland
Hey all, i have an 02 lb7, has about 202,000 miles on her. i run a ppe tuner on level 3 with a ppe boost valve and straight pipe.

before today i would have a very slight haze at idle, something you couldn't see unless you were really looking for it. and a bit of a lopey idle, its an inconsistent lope though, therefore i thought i might have a bad fpr.

also before today all my balance rates were in the +-.0x and +-1.xx except #3 injector which was -3.xx. and i read gm thresholds at idle was +-.0 to +-4.0 so i didn't think much of it (that's why i thought my fpr is bad)

anyway, so today was the day to pull the boat out so i put it on level 1 tune as to tow. i pull the boat out which trailer and all is about 12000 lbs and then drove 10 minutes to my house with one decent sized hill.

as i pull into my development i notice white/grey smoke rolling out of the exhaust and a rough idle. in neutral if i goose the throttle it turns grey/black and a decent size cloud also.

so i pop the hood and notice a ticking on the passenger side towards the cab. i then hooked up my tuner and #3 cylinder is at -6 balance rate

that doesn't seem like a big enough difference to be making the engine run so rough? would this be my problem? or would it be something else as well? i took the intake off and someone start the truck and quickly shut it off to see if the turbo spun freely and it does. i also checked the radiator hoses and they were not hard.

i didn't think that one bad injector only at -6 would make it smoke like that, especially blackish smoke under throttle. i though bad injectors was all white

i just want to make sure there's not something else wrong before i go start replacing injectors or an fpr, and if i do have to replace the injectors i was going to install 20% over injectors or should i got 30%. i read that 40% over injectors you need efilive to make a custom tune for them. thanks all in advance! i want to get this thing back on the road.
 

Rerywilson277

2002 LB7
Nov 7, 2013
25
0
0
Havre de Grace, Maryland
i bought the truck about a year ago with 194xxx, i called local chevy dealer and im getting my trucks mixed up but it was either 95xxx or 140xxx when they were replaced, i know that's a big difference in mileage but dont want to give you all the wrong mileage. if it makes enough difference i can call chevy monday and also ask what year they were replaced.

also i went out about an hour after this happened and started the truck and when i started it up it idled normally for about a minute or two and then started getting the rough idle and white smoke
 

dirtydmax

<---up shit creek
Sep 1, 2013
1,091
4
38
46
muskoka,Ont Canada
i bought the truck about a year ago with 194xxx, i called local chevy dealer and im getting my trucks mixed up but it was either 95xxx or 140xxx when they were replaced, i know that's a big difference in mileage but dont want to give you all the wrong mileage. if it makes enough difference i can call chevy monday and also ask what year they were replaced.

also i went out about an hour after this happened and started the truck and when i started it up it idled normally for about a minute or two and then started getting the rough idle and white smoke

That definitely sounds like a lb7 infector prob,i bet you will get a +-15 then a knock next,but it sure beats a bananad rod,hope you get her fixed:)
 

Rerywilson277

2002 LB7
Nov 7, 2013
25
0
0
Havre de Grace, Maryland
so if you could teach me real fast, what in the injector gets stuck or messes up all so suddenly, i thought when injectors go bad it slowly happens. i guess it all varies on different variables haha.

and why, if its injectors, that it only starts a knocking sound from the exhaust with white smoke and a ticking noise from the engine after it runs for a few minutes and warms up? i assumed if an injector was bad it would do it at any time.

anyway would you all recommend running a compression check before i purchase new injectors? and would 20% over injectors run well with ppe? or would i need efilive to compensate for them. thanks all, i appreciate the help
 

Rerywilson277

2002 LB7
Nov 7, 2013
25
0
0
Havre de Grace, Maryland
also 20% and 30% are the same price on thoroughbred diesel for $2736 for a set of 8. is 30% too big to run with ppe? where would you guys recommend getting injectors for the best price? i know i also need the rebuild kit with gaskets etc.
 

Bersaglieri

New member
Dec 28, 2013
82
0
0
i thought when injectors go bad it slowly happens. i guess it all varies on different variables haha.

Mine [injector] stuck open all of the sudden coasting to a stop in a 25mph zone. Went from no problems at all to knocking bad and black smoke. I fixed one and a week later another one stuck itself open. I have a love/hate relationship with my LB7...
 

dirtydmax

<---up shit creek
Sep 1, 2013
1,091
4
38
46
muskoka,Ont Canada
Mine [injector] stuck open all of the sudden coasting to a stop in a 25mph zone. Went from no problems at all to knocking bad and black smoke. I fixed one and a week later another one stuck itself open. I have a love/hate relationship with my LB7...

Haha,we all have that love hate thing .