QuestionQUESTION: My ford expedition 2007 model gives black smoke when I start it in the morning .black smoke usually comes out for 2 minutes.but I hav noticed one more thing when I switch off my ac the smoke decreases...i have checked all my oil levels they are fine ..i hope its not a major issue....and I have just got my service done.
ANSWER: Amrinder:
Black smoke suggests an over-rich air fuel ratio...in your case it sounds like a leaking cold startup valve or fuel injector since it occurs at startup only. However, since switching the ac off/on affects the smoke, then a possible problem with the control computer / automatic idle control (AIC) valve is indicated.
By the way,
Blue/grey smoke would indicate oil burning and white smoke is typically indicative of a cooling system/head gasket problem.
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QUESTION: The smoke is black..but black smoke also comes whem I am accelerating at around 2500 rpm .smoke also comes when car is at higher gear with lower speed..when I contacted ford agency they said catalytic filter is blocked soo they cleaned it...it was ok for some days buy again car started showing smoke..
AnswerYou should check the input air cleaner system for possible blockage which leads to the adverse [too much fuel, not enough air] condition. Also, as noted, the engine controller and fuel injectors should be checked for proper function as well as vacuum sensors and hoses.
As noted in my profile, my specific experience is limited to certain older SAABS..thus my suggestions are not specific for your FORD vehicle, but general.
