Q: Cost to fix: Spark plug #4 on passenger side blew out of its cylinder. Common on 5.4 Tritons. only need this spark plug 2000 Ford F150

Hi there. Unfortunately, this is a service that requires advanced machining tools; which our mobile mechanics don’t typically have access to on site. As such, it’s not a service we provide at YourMechanic.com. You might be better served contacting a local machine shop to inquire about this service.

Hello - you are correct that this is a chronic problem with this engine (Ford TSB 07–21–2). However, it is not simply a matter of putting another spark plug back in the cylinder head. In virtually all cases, the cylinder head threads are stripped, and a new spark plug will not torque properly, or remain in the head once the engine fires. Repair, if possible, involves a threaded insert into the damaged cylinder head. Unfortunately, this is not a repair YourMechanic can offer at this time. Consult your local Ford dealer or service center, or auto machine shop for this specialized repair.