When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
hey guys thanks for the replies on my first post. got another Q again my truck is an old 87 f150 4.9 300 straight 6 beater that im going to turn into a respectable work truck. when you first start it in the cold it idles good around 1000 rpm. but when it warms up after about 5 min it idles around 3000 rpm. i checked the vacuum resivor its not rusted all the way thru i dont think. my lines look are pretty dry rotted. is there anything else it could be like idle control motor. thanks for the help really helps talking to you guys!
carb or fuel injected? If it's fuel injected make sure you have coolant going into the throttle body, that helps warm the IAC, should be 2 small 3/8ths coolant hoses going to it, for some reason air always traps in there because it sits high in the engine compartment. If it's got a carb, and it has a solenoid that pushes out to raise idle make sure the lever on throttle where the solenoid touches is clean, sand down the throttle linkage and the solenoid, it makes a ground connection there so the solenoid knows it is hitting and controls the idle. Hope that helps, Good Luck