anerexic (pick word). I've been chasing a lack of power problem with limited time to check into it. Finally got a chance to drive it a good distance tonight for the first time and I think I figured out the problem. The manifolds were glowing a cherry red...so I now know it's running lean. Before I went through and replaced the passenger side valvecover gasket, it had the same no power problem. I didn't notice any vaccuum leaks after I buttoned her up, and most of the vaccuum lines were in good shape. Ruling out a vaccuum leak, what would cause the truck run lean enough to have BOTH manifolds a nice cherry red?

 

you need to pull codes www.fordfuelinjection.com will show you how. do this before replacing any sensors. but if the manifold is glowing i would say your cat converter is plugged up. if you remove the Y pipe from the exhaust manifold and drive it that way around your block and see if things improve.

 

not plugged I think, looked like a normal converter and the lack of power was still there with just the 1st cat only...I cut the second one off to make sure the first wasn't plugged as I thought that was the power loss issue. Exhaust system = stock 1st cat and a flowmaster 40 series with a turndown.

 

that cat could still be clogged and would explain the power loss. but regardless pull the codes if its running that lean something will show for it. i wouldnt drive it much , otherwise it may melt a piston