Just bought a used 08 with 44000 miles. When the truck is hot and stop to back in the driveway it starts knocking like its losing power. You can turn the truck off and restart it and it is fine. This past weekend I towed a 6 by 12 lightly loaded enclosed trailer in 70 degree weather and it ran fine until I stopped to pull the trailer in and it started doing it again. Could it be vapor locking ? I changed the fuel filter and ran a can of Sea Foam injector cleaner through it. The oil pressure gage does not move from normal and it is not light any of the warning lights. I traded a 99 f150 with 250300 miles on it and it never acted like this Help any ideas

 

I'm watching for some "good knowledge" along with you.

I have an '07 with 36K on it, never done what your's is doing .... yet (knock on wood). Almost sounds as if the ECM (truck's brain) thinks it's running hot .... like a sensor maybe acting up?

 

yep that what it acts like I am going to have someone scan it today and see if it shows up anything. One other thing it acts like it is idling alot lower than my 99 did. around 500 in gear and just a tick above 600 in park

 

Vapor lock went away with carburetors.

 

Scanned it today and nothing showed up. I am buying a scanner and hooking it up and running the truck until it starts acting up and see if anything shows. Right now I am grasping for straws. BTW I have already cleaned the MAF sensor with the proper cleaner, and the throttle body.

 

Just to be clear, it is a "knock" and not a sound similar to a deisel, correct?

 

It does sound like it is diesieling like back in the 70's when the vehicles woud not shut off and keep trying to run after the ignition was turned off but this just sounds like it is starving for gas? If you rev the engine something I hate to do when it does this it will clear out but the second you go back to idle it starts again. I can turn the switch off and restart it it 9 times out of 10 will be fine like nothing is wrong. if it did it all the time it would be eaiser to find but this once in a while crap without kicking a code is what is bothering me.

 

Search the forums for "cam phaser". See if that's your issue. You can also hear what some of them sound like on YouTube. If that's your issue the only specialty tool you need is the FR-303-1175-TD 3V timing chain locking wedge from Freedom Racing or the 303-1175 from OTC. http://www.shopfreedomracing.com/Timing-Chain-Locking-Wedge-FR-303-1175-TD-FR-303-1175-TD.htm is the best deal around and you can even rent them!

 

Ok I am starting to get Pi$$ed now! I changed the oil and put the 5w20 MC oil and MC filter and it is still doing it > Drive it about 10 to 15 miles in 70 degree weather and when you stop at a light or sit at idle waiting to turn it will start knocking. I pulled my 6by 12 lightly loaded enclosed trailer today and when I return home it started knocking it starts off soft and the longer it sits the louder it gets. I popped the hood and tried to pinpoint where the noise was coming from it seemed to be a little louder on the drivers side when I revved the engine it would quieten down so I just sat in the truck and tried different sthrottle settings after you revved the engine to 2 grand it would quit. Take your foot of the gas and it would start again when it got back to idle. It doesn't sounfd like it is the top end of the engine. The main thing is no check engine light or throwing any codes. I do not have any history on the truck but the only thing I could find out of the ordinary was after I got the truck home from buying it was the dipstick was rusted to the dipstick tube and the oil filler cap looked like it had a film of rust on the inside of the cap. I am at a loss I cannot get it to do this while at the dealer and I don't know what else to try. I have read somewhere on this forum that a pin sticking on the phaser that would cause something like this I am thinking about trying some type of engine flush maybe AutoRx and see if that would help. Or the next oil change adding some Lucas Oil Stabilizer. If anyone knows of anything else to look at please chime in I only have 15000 miles left on the powertrain warranty HELP

 

Cam phasers knock by design. I wouldn't worry about it. I've only seen one actually fail on this forum. Most of the guys who have changed them or had them changed did so just because they couldn't stand the noise, which is asinine. Dealers love to change noisy cam phasers. $$$

 

If it turns out to be the phaser your 5 yr 60,000 warranty should cover it. DO NOT USE LUCUS ANYTHING in these engines. No oil additives should be used in the 3v engines except for a very few which I can't remember right now, there is one with 'Regain' in it that seems to work well for cleaning only.

 

5/60 won't cover it if it's normal. And if it's deemed normal he's out a diagnostic fee. $$$

 

Service guy at a Ford dealership told me by the time the 08 models rolled around the phaser problem had been fixed? He also told me that when the phasers go bad they go bad not just every once in a while or when it's warm weather or is he just blowing smoke?

 

That's what I said. When they fail they fail, but they all make noise. Just search all the knock or cam phaser threads.

 

lets hope that poor truck never saw a fram "oil filter", if it did then you "warranty" is long gone