LB7: need a lb7 guru

[prorida]

I thought this was were all the big boys hang out at?
I NEED HELP DIAGNOSING A FRIENDS TRUCK. He has been driving like this for over eight months . He put's about 500 miles a week on the odo, and if he keeps it up he will be over 200k in no time, and lose any possibility of an injector warranty.

Symptoms... White smoke at idle. smells like fuel. he has changed his oil about three times with no fuel in the crankcase, and he hand calculates his mileage, and has not seen a drop.

i checked his balance rates and a few other things and this what i got. test done in drive at idle with efilive.
mm3 avg
cly1 -1.56
cly2 0.57
cly3 -0.03
cly4 4.36
cly5 0.80
cly6 0.69
cly7 -1.69
cly8 -2.96

the problem is i'm not sure what else to look at, like i said he has been driving like this for over half a year with out it failing. i'm not sure but i don't think those balance rates would warrant the amount of smoke it's blowing. i would love to hear your opinions, and thoughts. i plan on doing more tests when he comes through town on Friday.

 

[sweetdiesel]

Balance rates don't look bad excet number 4

Check to see if he is holding rail at idle and does it fluxuate bad

 

[MMLMM]

Those balance rates are near perfect except for number 4. Cyl 4 is adding extra fuel to keep up with the rest.

Hows the FPR? (whats the fuel pressure look like)

How much smoke are we talking out the exhaust?

 

[S Phinney]

The white smoke and fuel smell can't be diagnosed by Balance rates. If you have a way to turn up rail pressure at idle you can diagnose an injector that is by passing fuel which is what causes the smoke and fuel smell. Just turn it up a little at a time and you will see the smoke and smell go away. When turned back to normal idle pressures it will return in about ten seconds or so. It will take replacing the injectors to fix it.

 

[prorida]

his desired fuel rail pressure was 4931 his comm fuel pressure regulator flow was 2216. i'd like to do more tests when he passes through on friday. i don't have the neens to coddle me anymore. so i may have to pm one of you guys for directions on where to go.

and the smoke is noticeable, it won't barry the guy behind you, but it's more than a whisper. by the time it shifts to third it dissipates.