Usually when I stomp on the pedal above 40mph I get tons of acceleration and coal black smoke - I don't do this often, just often enough to know I can, but yesterday when I did it I happened to look in the rear mirror and I noticed the smoke was more of a brown color now. Still have plenty of acceleration but I was wondering what has changed. I sometimes use a Stanadyne additive in the winter but not using anything right now. Bad fuel? Bad injector? Timing changed? My imagination? I've been fueling up at the same place several months now and my only thought is that maybe they've switched over to winter blend and it's something in the fuel. Should I worry?

 

I think brown usually means your fuel/air ratio is close to correct. Black means more fuel than you can use. Have you changed your air filter recently?

 

or is your lift pump ticking?

 

Nothing out of the ordinary with the L pump - I oughta take the air cleaner out and clean & re-oil it though - it's probably been a while.

 

well, if you air/fuel ratio is closer to correct (as stated above) it probably has more to do with less fuel than more air. dunno.

 

Is it actually brown, or is the smoke just thinner?

 

Looked like it was putting out about the same amount of smoke as it always did, but it just looked lighter in color - kinda brownish.

 

On my old powerchoke when I ran dyed fuel in it it would put out more smoke and make it a lighter color almost a grey so maybe its something in the fuel like the additives for winter blend

 

I'm guessing winter fuels b/c here @ 4,000 ft with some cold winters the fuels get pretty crappy for quality, I use schaffers fuel additive RELIGIOUSLY #1 reason is my performance shop uses it in everything (i have schaffers atf in my tranny and transfer case)

#2 the fuel additive in my 1st gen gave me 4mpg by itself!! For the first tank I do a double dose when the first winter hits to make sure everything is lubed and clean. After than its 2 oz. per 9 gallons of diesel. Find a shop and just try it, if anything it might help your L pump by lubing it.

JMO