I had that problem with a 86 2.5L I-$ S-10. Number #2 would vibrate
lose. Problem was damged threads, but not stripped.
I bought a inexpensive K-D Tools 14 MM spark plug thread chaser. Pulled
all 4 spark plugs, chased the threads. Then I used a old stright boot
from a spark plug wire, and hand tightened the plugs down. Then torqued
them to the torque spec (I don't recall the number) with a torque wrench.
Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here.
All logos and trade names are the property of their respective owners.