1987 grandnational has high idle - 1987 Buick Regal

you will have to check for any vacuum leaks and check the EGR valve. if it stuck open due to dirt/carbon or just a sticky shaft it will cause a vacuum leak.

check your vacume hoses and if iyt has an idle controll valve that is off of the air intake. that should be the only things that would effect it

Usually it is a sticking throttle plate, vac leak, or a problem with the idle control valve.

Take the idle air control valve off and clean the carbon out of it with a non-chlronated brake ceaner then let dry 10 minutes and re-install.Reset the computer afterwards by disconnecting the ground cable on the battery for 30 seconds then re-install.

Check the throttle cable for binding and the engine for vacuum leaks.
You may have a stuck idle air control solenoid.
It is hard to say what it might be. Start running some tests and it will help narrow your search.

Sounds like you need W-D40 on all the movable parts of your carb. Also see what is blocking the butterfly to close all the way. Check the high idle linkage and see if it is properly closing all the way on warmup.

i have a 1987 buick grandnational and put a new fuel pump in and the car will run about 5 min then just shut off

Try lubricating the throttle body cable , sounds like it is sticking.

no, there is no idle screw on them if it is fuel injected. although you could try changing the idle air speed sensor

Check the timming it could be to fast that causes the motor to keep running its pre egnition.