high idle !!!

[blackhoss89]

I've got a 1989 ford bronco xlt with a 5.8 liter and an automatic tranny, when i start my truck it goes to idle around 1600 to 2100 rpm and im not sure why. I read another post on this website and the guy said he had the plenum gasket changed and it fixed his , our symptoms were similar and i was just wondering what the plenum gasket was ,where it went.how much it cost, and how easy it would be to fix by myself. thanks

 

[ole betsy]

I've got a 1989 ford bronco xlt with a 5.8 liter and an automatic tranny, when i start my truck it goes to idle around 1600 to 2100 rpm and im not sure why. I read another post on this website and the guy said he had the plenum gasket changed and it fixed his , our symptoms were similar and i was just wondering what the plenum gasket was ,where it went.how much it cost, and how easy it would be to fix by myself. thanks

it might be a broken vacuum line so i would check that first. but a plenum gasket is the gasket where your lower and upper intake meet. the gasket is pretty cheep, should be under $10. there is 5 bolts and a torx bolt holding the upper intake to the lower, youll have to unplug a couple of wires and 2 hoses going to your throttle body and unplug your vacuum lines on your upper intake. it should be fairly easy. good luck