black smoke

[hemimike]

I have thick black smoke coming from my exhaust,leaving black soot on the ground .The check engine light keeps coming on and off and the truck is very sluggish anyone have any idea what the problem is?

 

[Dan Whitaker]

Does the check engne light flash a certain amount of times (like 5 or 6) then stop & start again with the same sequence. If so you have a cylinder that is not firing.

It could be a bad plug wire or a bad injector. I would be willing to bet that a plug wire is bad.

The black soot is un-burned fuel (aka carbon).

 

[dogfriend]

Your truck is running very rich. When the Check Engine light comes on, one or several diagnostic codes are set and stored in the PCM. You need to have the codes read and find out what they are. I'm guessing that you will have several codes related to fuel trim (mixture) and O2 sensors.

 

[hemimike]

the light goes on and off while I'm driving ,someone mentioned the maf sensor can that have something to do with it ?

 

[dogfriend]

It could be the MAF or it could be something else, like a bad O2 sensor or a stuck injector. Getting the code(s) will help to narrow down the possibilities.

 

[hemimike]

yes it looks like I will have to get the codes unfortunatly it's about $100 to do that.

 

[dogfriend]

http://www.explorerforum.com/forums/showpost.php?p=1470344&postcount=4

http://www.explorerforum.com/forums/showthread.php?t=80903&highlight=voltmeter

http://www.explorerforum.com/forums/showthread.php?t=145746&highlight=voltmeter

 

[hemimike]

changed my maf problem fixed thanks for the info.