smoking, injectors, and ATF

[Outfitter17]

My 03 duramax seems to be smoking alot lot, but has been preforming just fine.

How do you know when your injectors are going bad? My truck starts easily, but idles a bit rough.

I have heard from others that if you put some ATF in your tank every 3-4 tank fills that you truck will idle, clean injectors and ultimately run smoother, is this true?

[Duramaster]

1st, what year, make and model truck are we talking about? 2nd, smoke from an LB7 in most cases indicates that the injectors have failed. Try to take it to a dealer and have them check the injector balance rates. Unless of course if you own your own Tech2, then you can check them yourself. Balance rates should be 0 +/- 4.5 mm3 at idle in P/N and 0 +/- 6.5 mm3 in gear. Hope this helps. ;)

[madmatt]

ATF in the fuel is an old timers myth and should not be used in these HPCR engines. As a matter of fact somewhere in your manual lists AFT in the fuel as one of the things not to do. ATF acts as primarialy a Friction modifier which is not something you want being pushed through your fuel system at over 25K psi. If it was good for the system, the oil companies would be advertising it.