Toyota Repair: emissions, fuel air mixture, vacuum lines

Question
Hello,
Just needing some help on an emissions question,
first let me say I have a 87 toyota 4x4 22R  it has 99,000 miles and still runs great best little truck I've ever had, but what I need to know is that my exhaust pipe puts out such a black soot and it didnt take long just put a new tail pipe and muffler on last week and its black sooty already,and it seem my oil turns dark within 800 miles after an oil change,I have a repair manual,its helped me to understand some things but heck figured you might know a good place to start for the problem, or that is what is common for that issue,anyway hope you can help, sure would be appreciated!
Thanks!
Bruce.

Answer
Bruce,

Does it have a carburetor or is it EFI fuel injection? Toyota had both in that year. The black soot means in running way to rich, that means the fuel/air mixture has a high percentage of fuel,
to much gas. It is not a common problem and it must be corrected.
It will really eat up fuel. Did someone mess around with any adjustments on the carb or throttle body? Are all the vacuum lines attached properly? Any broken vacuum lines? Is the air filter clean?

Tim
ToyDoc?