Idle is rough and rich after warming up 1986 toyota 4wdwagon 3 ac

Was the fuel drained out and flushed ? The engine coolant temperature sensor may be bad and reading too low causing an overly rich mixture .

Bad carb or fuel injection issues- the system is fuel rich (black smoke) and also fuel rich system can make the idle low. Many things can cause this but thses are just a few.

you need to adjust your idle screw on your carb i could tell ya how on that type of car but your running to high of an idle and flooding your cylinders thats y it is idleing rough and you can smell the gas, adjust your idle screw back a little and then you might want to check your plugs and make sure you didnt fowl and of them with it running rich

Hi,
Please 1-check the PVC Valve. Block off the PCV valve and see if the miss goes away. If it does; replace it.
2-The other thing is to check the plugs to be SURE 100% SURE - they are factory rated for that engine. 3-check the fuel filter.
4-Remove the negative battery cable and give the on board computer 20 minutes - then re-connect and run the motor 20 minutes for the engine to adjust to the new settings.
5-Lastly if nothing else works -I will simply suggest a compression test - sounds like a valve may not have seated perfectly or is burnt.

Look on the side of the carb.There should be a couple of solenoids mounted.one of them is not working.Check for a blown fuse,and also take the solenoids out and clean,and reinstall.If this does not work,then find out which one is not working,and replace it.

If it is a carb engine have the air fuel mixture corrected by adjusting the screws on the carb. Try also adjusting the idling.

For EFI engines see if you can check the Idle Control Solenoid Valve, have it cleaned. You can also check the oxygen sensor if it is working or not

you can take apart the top section and blow out the small passage that's bellow the throttle plate.

does it have a cold start injector seperate from the other injectors usually on the upper intake somewhere with a fuel line going to it

I think you must have the carburettor plunger not going well as you are getting flat spots under sudden acceleration, I think the best way to go is to get the carburettor overhauled.

if it is a carburated engine it is probably the a.a.p. diaphragm in the carb. if you remove the air cleaner and look on the side of the carb that is towards the valve cover near the front yow will see a vacuum hose going to a cover that is fastened with 3 screws. if you pull the vacuum line off you will see that there is probably fuel being sucked into the line due to the leaking diaphragm. the vacuum source is temp controlled and cuts off when warm. but when cold sucks fuel directly into the intake. remove the 3 screws to replace the diaphragm, being carefull of the spring. good luck!