Won't idle properly

When you give it gas ,will it rev up?skip?

Most of the time no. Runs fine above and idle and is not as bad when the engine is at or above 175.

Have you changed plug,s wire,s etc.?

Not in quite a while, cap and rotor change just over a year ago. Same with the plugs. The engine lite does not come on. SHould the vacuum line from the throttle body to the canister have vacuum all the time? All other lines have good vacuum?

Should pull vacume as truck idle increase,s.Check cap and rotor button.

Distributor,s in that year model tend to act up all so,if it has not been changed can cause this.

One last thing to add,if it has a control module on distributor,check it all so.

No module on the distributor but when it cools down I will take a look at the cap and rotor. Thnx