Ok so I have the 2009 f150 4.6l 2wd. Have random misfire codes. Horrid idle. I replaced all of the spark plugs, coil packs, and even the injectors on 1/3/4. Still codes nothing is better. I'm thinking maybe an intake manifold leak,? I see no real signs but I do hear that little pop pop pop. Now I have a gasket kit for it but I see you can order complete manifold kits with thermostat and gaskets on amazon for like 60 bucks more. The issue is I see none that fit my truck. Is it the same as the mustang? Hate to blow more cash as its adding up. Anything else it could be?

Have codes 301 303 304

 

I believe manifold is different than Mustang. Did you use Motorcraft coils?

 

Yeah I ordered all parts from ford parts. So all is motorcraft. This issue has me baffled. Tried the carb cleaner around manifold as well no difference...

 

"Anything else it could be? "

Did you check the PCV hose for a vacuum leak?

 

Thanks for info. I changed intake gasket it wAs damaged and helped a lot. But still had issues with cyl 3 1 and 4 cleared up. Turns out to be cyl 3 had blown a plug 8 months ago well the insert and plughave melted and I need a new head. (Yes same week old plug) Of course I have the stupid motor nobody makes parts for so a new head at ford is 1400. Or i get a complete crate rebuilt engine for 2900 through ford. As im up to 140k and have a brand new tranny and rear end I think I just might opt for the new engine. They claim they have updated heads that dont have the blown plug issue.... we will see. Thanks for the help!

 

Yes I would go for the engine with a warranty.

Steel inserts in an aluminum head do not work well because of the heat transfer, it needs an aluminum insert. Lock n Stitch is now the Ford approved method.

 

Cool good to know. Yeah warranty would be great. I knew the insert needed to be aluminum but I was in the middle of bfe on a work trip when it blew. I was just happy to have it fixed and get home.... so my bandaid worked 8 months. And I forgot all about it. I guess I cant complain...

 

At least most of the parts you bought will transfer over to the new engine.

Hope it goes well and welcome to FTE.