It's deffinately carbon, it is not oil. It washes off the pavement with a garden hose.

Seems to happen all the time. It does not happen more on start up. Or does not happen more after being driven for a while.

It is not throwing any codes.

Recently checked the AFM and it tested good.

I have not changed the O2 sensor since I have had it.

I unplugged the cold start injector and it still does it.

Any ideas of where to start?

Thanks

 

Hey, that's what our FJ40 does. How's your cat? Other thing I'd check is your O2 sensor.

 

Your exhaust system is worn out and rotting from the inside out.

 

yeah id say the O2's or the cat.. maybe every part of the exhaust.. does your exhaust stink when everything is on?

 

Cat was punched out when I put the new exhaust on. The only part of the exhaust that is left from when I bough it 6 months ago is the manifold, and the down pipe. Both look good from the outside. I just put new manifold flange gaskets in today, and the inside of the down pipe and manifold looked good from what I could see. I guess I could take the cat off and put in a piece of pipe to see if it is coming from that.

Exhaust is origional manifold and down pipe, cat punched out, 2.25 pipe new to flowmaster series 40, 2.25 out the back.

exhaust does not stink.

also that is only from about 5 minutes of running.

Thanks for the thoughts on the exhaust though.

I will see if AZ has a O2 sensor tomorrow.

 

My 84 does that. It always has, but I bought it without a cat on it so I am assuming that is the issue. It runs great and gets great mpg too.

 

I would run some sea foam through the engine to clean out any carbon build up and then replace the 02 sensor.

 

It should be nothing to worry about. Just condensation collecting the carbon and spitting out when you are running. Typical of a truck without cat.

 

that really normal.