in response to my earlier question mr carpenter said a black tailpipe does not mean running rich.i used mr carpenter because i am new to forum and don't want to offend.i have read some posts that got out of hand.what will make a 2005 5.4 that was clean and there are a bunch here around dallas tx that are clean change to running black after dealer replaced cam timing sensor?please throw some stuff my way i don't understand.thanks for any help.

 

I don't offend very easy..As a matter of fact hardly at all..Marc will do fine.
I am not saying that lean burn will not blacken your tail pipe, but the new unleaded fuels just don't have the additives in them anymore (lead) that create that nice off white chalky surface we all had with our 60's muscle cars exhaust. It is possible that you are running a little fat (rich) after the repairs. The best way to tell is get some Air Fuel ratios. Is there a good dyno in your area?

 

The black tail pipe on mine depends on the fuel. Seems like Shell is more prone to black up the tail pipe. But I have a tuner and run a little richer over stock.

Considering these trucks tend to lean out from the factory, I'd live with the black tail pipe. Rather have a bit rich over lean.

 

thanks for the replies and i don't know of any dyno's around here much less a good one.it was alot easier in the 70's before unleaded gas.dyno i don't need no stinking dyno.it either pulled the front wheels off the ground or fell on its face.question to Marc if the shifting was acting up at around 4200 rpm just wanting to stay at 4200 and not really rapping up any more and have to let up to get to shift.getting a custom tune or programmer going to clear this up or is it in the pcm which needs to be looked at.i guess it could be the trans but only does at wot.i just hate to take back to dealer they seem to mess something else up when i take it in for anything.

 

Mine is stock and I use shell every fillup and have no black tailpipe deposits.

 

you have a problem, probably transmission related. a programmer & custom tune will not likely fix this issue... it's not the magic answer and will either compound it or mask it til further, more extensive damage occurs. but any knowledgeable tuner like troyer will tell you to fix any problems like this first, THEN do the mods like tuning.