choke puzzle
 

hi! I've been having a problem with my 05 f150 5.4 lariat 61k on it. when I hit about 45-50 mph the engine "chokes" or "putters" like sort of a "cough" or something, until i let go of the gas. Its happened to me a couple times, not every day and not again the same day. I took it to the dealer where they fixed I dont know what??? and never solved my problem, the next day it did worse so they said they cant diagnose unless the engine light goes off but i hate waiting for things to get worse. these guys acted like they've never heard of such a problem before. they changed some sensors did some timing thing, and said "that should do it" I'm under extended warranty 100k. I appreciate the help, thanks

when this occurs, is it while under a "load", or just slight throttle..... is it while the overdrive is on? it almost sounds like a bad COP. when it happens if you give it more throttle to downshift, will it still happen or clear up?

there is a TSB for 05's with bad injectors. I think this or the COP is your most likely culprit.

keep us updated, wish I could help you more

choke puzzle
<HR>My 08 has 12000 kms on it and it does the same thing. Sometimes between 40-50 mph, the truck "putters/flutters" when under load. Then if I let go of the throttle or hammers on it it clears up. Also the CEL doesn't come on. I have no idea what the problem is but it is really starting to bug me. What is a COP?

Mike

Coil On Plug or something to that effect.