hey guys teh exhaust in my cb gsr has a lot of black carbon build up so it looks a little weedy could this be either a problem with a heat sensor in the block so the car thinks its always cold? or dirty injectors causing a bad spray pattern

 

think about it the thermostat has nothing to with the exhuast system. your probably burning some oil cause you over filled it.
or you haven't tuned your car in awhile. why don't you buy a bottle of injector cleaner and pour in your gas tank and see if that does the trick.

 

i heard to fix that on the CB lancer (1.8) to run the injector cleaner but don't quote me, as i don't own one!! prolly best to see a predy good mechanic n ask him