what would cause black smoke to billow out of my exhaust? on 1991 Toyota 4 runner 6 cylinder 4 wheel drive?

Answer 1

black smoke means your running really rich, you most likley have a leaky injector or bad plug/wire your dumping raw fuel and not burning it hence the black smoke.

Answer 2

black smoke means that rich in fuel /lack of air. so check if the air filter is clean. check if the injector is not dripping . then check if the engine is able to take up the load & the temperature of the crank case is within limits. if not then go for a compression test to know if there is a blowpass.

Answer 3

All 4 wheels are powering your Jeep yet once you unfastened traction then the wheel with the least traction can spin. this is one front and one rear, the two section. The function of a Posi or constrained slip etc. is to attempt and save the two rear wheels turning for the period of low traction situations. Spools or lockers certainly lock the two wheels at the same time yet it somewhat isn't a good way tocontinual on stressful surfaces because of the fact the wheels might desire to teach at different speeds once you bypass around a corner. this is the place the differential gets its call.

Answer 4

Finally a question about black smoke and not many are saying burning oil ! the air/fuel mixture on your vehicle is too rich .

Answer 5

Common question for 1st year mechanic students or at a job interview.
Its running rich.Change the air Filter!
If it continues check the injectors.

Answer 6

To correct Eric H, if you were burning oil it would be White smoke, coming from your tailpipe. I agree with everyone else, black is a fuel issue.

Answer 7

Stuck choke on your carb, if its fuel injected a stuck injector

a plugged air filter

Answer 8

id say that your burning oil. Have a mechanic do a comprssion test ($50)