..Exhaust Question???

[hardbody90]

my truck doesnt really smoke its like minor until i like rev it up.. what causes this?.. also its really black inside my muffler and when i rev it up it seems to spit out moisture coverd in black stuff also.. didnt know if this is normal or not.. any suggestions would be appreviated.. thanks

[RT]

1 if it smokes a bit on start up and stops once it runs a minute, it may be the valve guides leaking a little oil into cylinder when oil is on top of valve train after running. Oil runs back into crankcase and some may leak by valve guide. Typical on high mileage cars and trucks, watch oil use, it will not move on dipstick between oil changes. This is normal. Black soot on tip means a rich mixture on start up most likely again typical on high mileage stuff. Tune up may help but if truck is running good and mileage good no worries. The water is just condensation in exhaust and once engine is warm it should stop spitting water. ALL cars do this in the south when humidity is high, water condenses in exhaust when sitting and spits it out in first few minutes of running. Sounds normal on all fronts for older trucks with some miles on them.

[Nitewulf]

Parts one and two I agree with, however, you can have water in the exhaust long afer startup. if left idling for a long period of time after it has been hot from running, you can still develope moisture in your exhaust. Which as stated is a normal condition, though it seems strange that you could develope moisture in a high temp metal casing, the amount of cooling from the catalyst and your egr puts enough fresh air back in the system to produce moisture in the exhaust. On header or straight piped vehicles it isnt really a factor, due to the lack of the external air forced into the exhaust system.

[PEZi]

it could also be in need of a tune up. when i first bought my truck it did this. a change of dist cap wires and plugs and it was gone.

[C-Kwik]

Could just be water as water is one of the products of combustion of any hydrocarbon. If its hot enough, it will not be seen as it will be a vapor, but if it has an opportunity to cool down enough as it makes its way through the exhaust system, it can become a liquid.