I recently put an exhaust and air intake on my 2006 f-150. Just the other day I went to hammer on it and it started missing for a second, it was popping for a second before it caught up and took off. It sounded like a metallic popcorn pop. Right away I thought this was because it was running lean from the CAI so I put the stock intake back on. However it is still doing it, only it's not as pronounced as the stock air intake muffles it more. It only does this under heavy acceleration, usually around 3000-4000 rpms and makes no noise when just reving the engine in neutral. Anybody have any ideas? Was thinking possibly a bad injector or something screwed up with the mass airflow sensor?

Any help much appreciated
Zane

 

did you get a custom tune for that intake? if yes then i'd check that first.
if no then whats the mileage? has the engine ever been tore apart for anything? i know this is a stupid question but it may help us, when you put the intake on, was it raining? have the plugs ever been changed? coils ever been changed? what kind of intake did you get anyways? if it was an oil charged filter then i'd clean the maf. the oil from the filters contaminate the maf and causes alot of issues. and the 05 5.4s had a bad batch of injectors and they were warrantied for 100000 miles, some 06's have the bad injectors too but they arent warrantied. so you may have a bad injector or possibly a dirty injector

 

Nope I have a tune from Troyer on the way. I had the intake on for a couple weeks with no tune and didn't notice a problem, its a K&N 63-2557 I think, then this started happening and I put the stock back on, which didn't stop it. The truck has 77,000 miles and when I put it was relativley dry, as far as I know the coils and plugs haven't been changed. I was thinking the injector thing as well but the MAF could be screwed up, though I never sprayed any oil on the filter. Is there a way to test the MAF? Whatever it is I think it is in some way/shape/form connected to putting on the intake. Any thoughts?

Thanks again for all the advice it is very appreciated
Zane

 

you were probably running too lean(but within specs) and it may have wasted the plugs. but i'd clean the maf, and replace the plugs and see what you got. running lean doesnt help the plugs at all or the coils.

 

Mine does the same thing and I've never had an intake on it, just exhaust. Not sure what it is and don't really have the scratch to put it in the shop right now.

 

Just got it back from the dealer, needs new plugs. With the CAI on it it was running lean and guessing the plugs were already gettin a little old so that did them in. And get this, dealer wanted $610 to replace the plugs, couldn't believe it, then $60 a pop for each plug that broke on top of that. Needless to say I won't be going back to that dealer anytime soon. Gonna get the stuff and do it myself, partlly to save money, partly to spite the mechanics at this place.

 

Do you know what you are getting into changing the plugs? Good luck, please tell us how many you break.

That quote is not unreasonable.

HINT: Read the Ford TSB on changing 5.4 3V plugs.................................