2001 Ford Expedition

Transmission problem
2001 Ford Expedition V8 Automatic 11200 miles

everytime my husband crank up his 2001 ford expedition black smoke comes from the tail pipe. He also says it aile up too high and it jerks while driving.

He took his car to have tune-up, but nothing changed. They told him that he need to drive it to get all the smoke out. Seven day later there still smoke.

Today he took it for diagnostic, that show differtials with the rear-end, but everything I'm reading about differtials does not add up. No clinking sounds, no leaking fluids.

Please give me your opinion.


April 18, 2009.

You are correct, the differential has nothing to do with the black smoke. Black smoke indicates too rich of a fuel mixture and not enough air. Start with the simple things. Make sure the air filter is clean and there is nothing blocking air from the engine. If all is ok, move to the temp sensor. If it is telling the computer it is colder outside than it actually is, it will over compensate the fuel mixture and provide too much gas to the engine.

Last is the fuel injector system. The pressure regulator could be allowing too much pressure to the injectors. You would need to check fuel pump pressure. Here is a how to video for checking pressure:

Let me know what you find.


Thank you so much for your respone. Could bad gas cause black smoke from the mufflers?

Apr 20, 2009.
If you have old fuel or something that isn't good, yes it could cause this too.