First post as I have looked everywhere online and can't find a thread or YouTube video describing what I'm experiencing . I have a 2010 F150 Fx4 5.4L (195,000 km's) and my biggest problem I'm having is that when I start the truck , it just continues to turn over and over and over and shake a bit before finally barely starting up . A ton of exhaust comes out the tailpipe before the idle settles down . Once the truck does fire up, if I shut it off and try to fire it up again , it fires up immediately . Only after it has sat for 4-6 hours does it do the shuttering startup . I had the fuel pump and sending unit replaced thinking maybe it was having a hard time getting fuel . I did the spark plugs myself last summer with no problems , I didn't however replace the coils . I know 5.4's are notorious for timing problems and solenoids , and I have only once had the truck shutter and knock at idle while through a drive through so I know the solenoids probabaly need replacing . Does anyone have any advice on what to go to next? i hope it's just coils for now . I've done a lot of research on these engines and can diagnose a lot of problems but that has me STUMPED. Thanks

 

Codes?

 

Could be too much fuel - flooding - due to leaky injectors.

 

Roadie - getting codes read tomorrow - also the exhaust smells pretty fowl , my guess is that it's turning over and getting too much fuel trying to startup which explains all the exhaust , but why is it turning over and over and over and not firing ? That's why im thinking its coils . Just find it odd that it only does that after it's sat for a few hours - if I run to the store and back it starts up no problem after the initial crappy startup. Thanks for the replies guys , this has me stumped .

 

There are a couple of sensors that tell the computer the engine is cold and causes the fuel injectors to pulse longer. Maybe one of those sensors.

 

If the injectors are leaking, it takes time after you shut it down for them to bleed down into the cylinders - if this is what's happening you are very close to having a hydrolock. Does it start if you hold the pedal to the floor?

 

stopped by my mechanics today and the only codes that were pulled involved the cam sensors , I had an incident a few weeks ago where the truck shook while idling at a drive thru which I figured would be VCT solenoids or phasers .. it's a 5.4.. I knew that was coming , but nothing that points to the rough start. Then I showed him a video of the rough startup with the smoke from the exhaust and he believes my head gasket is leaking . I bought some iron tite today , I'll post if that changes anything over the next few days .

 

after talking to my mechanic today he seemed to rule out injectors , who knows for certain really , but he felt pretty confident in saying the injectors were functioning properly . I use injector cleaner every couple of oil changes just to trunk stay on top of it .