This is driving me crazy. I have a 1999 F150 w/5.4. I have had the truck since March 27 and it has been in the shop 3 weeks so far. It has a brand new crate motor because of the leaky head gasket and the motor has about 1400 miles on it. It shakes like crazy when at idle and it is really pissing me off. I have taken it to the dealer 2 times now and no relief. They checked the plugs, coils, re-flashed the computer, supposedly replaced some hose for a vaccuum leak, re-positioned the motor mounts, and supposedly checked all the other sensors also. Still it shakes at idle. Is this something I just need to learn to live with? I never get a check engine light and the truck runs fine otherwise. I am taking it back to the dealer tomorrow. Does anyone have any suggestions? Thanks in advance. I am starting to regret purchasing this truck.

 

Some of the 1999 Lightnings(5.4L) have had a problem with the fuel line coming loose at one of the f/i pumps(inside the gas tank). I think the hose clamp was the culprit. But you say it runs fine other than the rough idle so I d/k???

I also suspect the installation of the crate eng. They may have left off a hidden vacuum hose...............

Dan