× Auto Repair Pros Member Benefits TechHelp Knowledge Base Forums Resources My iATN Marketplace Chat Pricing About Us Join Industry Sponsors Video Members Only Repair Shops Auto Pro Careers Auto Pro Reviews
Join Now
International Automotive Technicians Network
Re: 1990 Ford F150 4.9 missfire
Posted to Technical Theory Forum on 1/22/2007

[...trimmed text...]

Hi Doyle,

A misfire like this can be hard to find, I would carfully analyze the ignition patterns and look for signs of valve leakage. An exhaust valve leaking may be hard to catch on a secondary pa... Login to read more.