LLY: smell, smoke hard throttle

[oldwrench]

newbie hear
just got my first duramax, 05 LLY. runs great with a couple of exception, and looking for some insight.

1. on light throttle, like maneuvering in a parking lot or trying to inch into traffic, it hesitates and just doesn't seem to want to go until you give it a little more throttle and it takes off. other than that it performs great.

2. it smells. like raw diesel fuel from the exhaust, but no smoke at idle. but when i am on the highway and lean on the throttle there is a lot of black smoke

the truck is totally stock from what i can tell. original exhaust, and no other visible mods. i suspected fuel pressure relief or injector but have checked fuel rail pressure and cyl. balance and it all looks good. and it runs super strong.

any suggestions of what to look at next would be appreciated.

Jon

 

[joshd472]

Raw fuel smell is normally injectors.

 

[oldwrench]

is there a way to test injectors other than cyl balance?

Jon

 

[TheBac]

Moved to LLY section of Hard Parts.

Yeah, sounds like injectors. At least you've got an LLY....a lot easier to replace them.

 

[joshd472]

is there a way to test injectors other than cyl balance?

Jon

A return test.

 

[oldwrench]

an update; found a great thread about the proper way to check balance rates in this forum, so when i went to check it i found the engine never got above 150 deg. so 2 thermostats later the smoke and stink are gone. thanks for the info P.S. 2 injectors borderline

 

[oldwrench]

oh ya still haven't found a resilution to the tip in throttle hesitation, if anyone has any ideas.