• Hello there guest and Welcome to Fox Body Mustangs forum, This forum is intended to be used by enthusiasts of the Fox body Ford Mustangs (1979-1993)!
    To gain full access you must Register. Registration is free and it takes only a few moments to complete.
    Already a member? Login here then!

Lifter ticking and misfiring, but only when hot


New Member
I have an '87 5.0 with about 140k on it. It's been running like a dream for 4 years, suddenly the motor started choking like a single cylinder misfire and ticking loudly from one valve cover. When I start it cold it runs very smooth, but after it warms up I get these symptoms. It sound like a bad lifter, rocker, or a bad valve. Can anybody explain why it only does this at operating tempurature?

For now, I just want to replace the worn components. If I have to replace the cam (depending on the condition of the lifters when I pull them out) I will probably just get some cheap racing heads with it. Roller sets seem popular but I've been getting 30mpg on the highway and I dont really want less. If anyone has advice for increased flow + original or better fuel efficiency I would love to hear how you did it.