86 ranger engine vibrate when hot

86 ranger, 2.3L,FI, AT,156K. I posted a question a while back and the problem was the engine dies when I shift from park to drive after startup and also when on stop mode waiting for the go signal. I was advised to clean the throttle plate and did that. I remove the whole throttle body/plate off the top of engine and clean it good and then put it back together. I also cleaned the AIC which is attached to the side of the air filter housing(my AIC is not attached to the throttle body). However, it did not correct the problem. Now, another issue came up. The engine vibrate and shakes after driving for about 20 minutes or when the engine gets hot. It will only do that when the engine gets hot, not when when the engine is cold. As if it's out of timing. But it starts good and runs well when I first drive it in the morning going to and after work from the park and ride, about ten minutes from my house. I replace the plugs and rotors and did not help. Please help.

do you have an auto choke? sounds like the choke is not working correctly on the carb.

Check all your vacuum hoses for leaks

thanks for your response. How do I check for vacuum leaks. When I cleaned throttle body, I remove all the vacuum hose attached to the top of the throttle body, labelled it, and put it back as labelled. Please guide me on how to check for vacuum leak, I'm a newbie.

All of the vacuum lines start at the intake manifold. Listen for a whistling sound which you will hear if a vacuum line is leaking. When I check for leaking vacuum lines I start by pinching off the lines at the intake. If one is leaking the motor will sound different when the line is pinched with a pair of needle nose pliers. Then you can trace the line back to where it goes to see if it is leaking at that point. If it runs good when it is cold and doesn't run good when it is hot it could be a vacuum leak.