2013 3.7 f150 stx strange noise coming from engine
 

When i accelerate hard or when I'm driving up a hill or towing a trailer the truck makes a rattling clicking sound in the engine. It's loud enough that i can hear it with the radio up. My passenger noted it could be the timing or bad gas. I switched gas to a higher octane and filled up at a different gas station, made no difference at all. The truck doesn't smoke or lose power when the noise is present so that rules out the timing. I crawled under the truck and found nothing loose. I also put it in neutral and revved it up, no noise. I am out of ideas of what this could be. If anyone has had this happen to them please feel free to share with me what you found, thanks!

Maybe check for exhaust leaks?

I did check the exhaust everything was tight no holes or cracks or anything. It's definitely in the engine sounds like a bad gas sound or a stalling sound. You think it would smoke or throw a code but it doesn't. It's very strange especially in a truck with a little under 25,000 miles on it.

I did check the exhaust everything was tight no holes or cracks or anything. It's definitely in the engine sounds like a bad gas sound or a stalling sound. You think it would smoke or throw a code but it doesn't. It's very strange especially in a truck with a little under 25,000 miles on it

Might have issues with the VVT sensor going bad but It should be throwing a code if that is the issue. The Variable Valve Timing sensors are on the front of the valve covers. You could disconnect them and see if that changes anything. If it does, you've located the problem. But normally, these are not an issues with this engine. I assume you're keeping the oil changed and using the right oil. The system works off of the oil pressure.

Wouldn't hurt to put a couple bottles of Chevron Techron in the gas tank. As combustion products build up on the pistons, it has the effect of increasing compression. This probably isn't the primary cause of your issue but it might help a little.

I took the truck back to the Ford dealership and they are saying it's my k&n cold air intake causing my truck to run lean. And that i need to get it tuned. All my friends have newer Ford trucks and use them with no problem at all. And i have used them on all my trucks and cars with 0 problems and i never had any of them tuned. I think i was sold a lemon!

Thanks for your feedback much appreciated!

The K&N is a known issue with any of the newer trucks. The new trucks come with a factory cold air box already. You spent money and got nothing for it. Yes, the dealership is correct, you don't need to tune the the truck, you need a tuner to adjust the A/F on the it. The K&N is also known for having holes in the gauze over 40 microns in size. It's also responsible for fouling the sensors in the intake with oil that migrates there. The dirt that the K&N filter allows to go thru it can and will damage the engine. A micron is 1/1,000,000th of a meter. The fix for your engine is throw the K&N garbage away and put the stock box back on it. The truck isn't the problem.....

Nope, it's not a lemon. Get rid of that K&N. Even with a tune it's not doing anything but making noise and letting more fine dust and warm air through. The stock intake is a very efficient cold air intake. It's causing it to run lean because the MAF sensor is not in the same place as stock and it's misreporting the amount of air coming through. If you INSIST on keeping that POS intake, you MUST get a tune. Evidently neither you or any friends have owned a F-150 with a 5.4 3 valve, a K&N without a tune on those causes burned valves it runs so lean.

Can't blame Ford for something YOU caused. Be glad they didn't void your warranty.