What would happen if platinum plugs were installed instead of iridium? I just had my 60,000 mile work done at a local mechanic who seems very competent and is into Subaru's and I'm pretty sure he said he installed double platinum. Also, what effect do spark plugs have on fuel efficiency?
Spark Plug Install Instructions
in Walkthroughs :: Basic Operation & Maintenance
Posted · Edited by J33DMB