My 2007, 5.4L, FX4 has been sputtering when I accelerate. It seems to do it the most between 40-50 mph. It also only does it when I am accelerating slowly, never when I punch it and the truck down shifts. It does not happen very often, maybe once a week or so, but when it does do it, it is very noticeable. Any Ideas what the problem might be. Thanks.

Justin

 

How many miles on the truck. Stock tires?

 

my 05 is doing the same... i did have one bad injector, but you'd smell the gas... the miss you have is the same... 50mph... rmps about 1900...miss..really noticeable.........COILS ........thats your issue...

i got 10 off ebay for 109 shipped to the house.... ford wants 85$ each... so figure 550 in parts, then 300 in labor.... . f that.... 100 DIY..!

good luck..... coils and injectors are a killer on this yr truck!.

 

How many miles since fuel filter was changed?


Also, clean the MAF and trottle body.

 

If it has more than 60k on it, you are due for new spark plugs.

 

I have 88,000 Miles on it and have Nito terra Grappler tires on it. I have never had the fuel filter changed or spark plugs. I pretty much just keep the oil changed and replace the air filter about twice a year thats it.

 

I would start here.

My truck had a similar issue a while back. Changed the plugs, fuel filter, cleaned MAF and throttle body. I havent had a problem since.

 

88k and you have never changed the fuel filter??????

That's pretty poor maintenance, that should be changed every 30k. Haven't you ever looked at the maintenance schedule that came with the owner's manual?

 

change your fuel filter....don't pay the dealer they want $85 and its a $17 part. How To's on how to get it off and deal with the clips...took me about 10 mins total.

have your spark plugs changed, read up on the broken plug threads if you are going to tackle it yourself. (The two piece plug will break off and fall in the engine)

You either have an injector that is going out (warrantied thru Ford to 120K miles) I had #7 sick wide open but you could def tell. Truck spit out black smoke, raw fuel and felt like a funny car on the drag strip. Ford will replace for free, be carefull you don't drive with it stuck as you can damage the engine severely)

Change your COPS. I changed mine out after I had a shudder at stoplights on occasion and no codes were thrown. I went with Global COPS from Ebay for $110 and changed them out, no problems since. Ford wants $85 a COP which is nuts.

and clean your MAF sensor, takes about 3 minutes and a monkey could do it (how to section as well)

 

Not on an 07.