4runner 88 3.0 rought idle and black smoke

[stevent]

Hi guys i recently bought a 4runner 88.the first sign:On the highway he suddently decelerate without any power.When i stoped pushing gaz pedal it went back ok.the truck died on any stop.i got to restart it everytime i stop.Today the truck begin to go worse.When i start it the idle is rought and under 600rpm and the exausht puff black. i changed the fuel filter and cleaned the throttle body and it didnt help =(.I did also a seafoam see if it would help...but no chance. Any idea wat it can be???

Sry for my spelling im doing my best im not an english speaker .

 

[KidVermicious]

Black smoke and a rough idle tells me you've got unburned fuel due to one or more cylinders not firing properly. I'd do plugs and wires next (post up pictures of the plugs, they'll tell you if one cylinder in particular is missing), check the air filter, maybe check the distributor cap too (does the 3.0 have a distributor?). Swap out the O2 sensors, and make sure you don't have a leak in the intake boot. If it's still rough, check the timing. Check for leaks around the injectors. It's good to rule out the easy stuff before you go looking for trouble.

Check the engine codes, even if your engine light isn't on, there may be stored codes that can tell you something.