ColeLarry

You are incorrect. Spark knock can be harmful and should not be ignored. Please tell me your qualifications and how you "know these engines."

Z7What

Knock and Detonation is the same thing! It's preignition of the fuel. Knock/Pinging is the sound that Detonation makes.

BTW, I have a 2013 F-150 5.0L. It currently has 22K. I have a Airaid Jr Intake(just the tube, still running stock air filter), Resonator Deleted, and a 87 Performance Tune. Been having all 3 of those mods since the truck had less than 3K miles. Also have run only Shell E10 87 and never have had ANY of the issues y'all are describing.

Wayne

Donutz

Hahaha spark knock and detonation are not the same thing!!!!!!

Everyone!!! These are the people that u are getting mechanical advice from???!!!

I will say it one last time...... Detonation is an explosion its the sound of the fuel air mixture exploding instead of burning in a fluid manner..... Sounds like a loud knock.....this will wreck your engine. spark knock is the sound of two flames colliding in the combustion chamber and sounds like a series of ticks. Will not hurt the 5.0. It is designed to be lean in hotter weather. Use midgrade or premium fuel in the summer and it will not happen.


If you want sound advice. Ask an engineer or someone that has a clue about engines.....not these fools

Good lord

ncgator8

Golly, a lot of opinion here. I encourage each of you to review this link: http://en.wikipedia.org/wiki/Engine_knocking . Maybe this will help a little. The short of it: the modern engine is supposed to control spark advance, fuel mixture, etc. by computer to eliminate spark knock. An occasional slight ping is one thing; beyond that, eventually, I believe you will shorten the life of your engine. Try buying better gasoline first- not necessarily higher octane, but top- tier fuel (something else to look up if you are unfamiliar with it). Add a good fuel system cleaner, such as Lucas or Seafoam (I prefer Lucas, but others swear by Seafoam). The engine could be carboned up, depending on how it has been driven. This is very hard to diagnose short of taking off the intake manifold, because there is no computer code, no sensor that will indicate this. I had a situation like this on a Corvette once that had apparently been driven in town all of its life. After spending the money for new spark knock sensors, I discovered that the intake ports were really carboned up badly. Two bottles of Lucas cleaned it all up- no more knocking! If these things do not clear it up, get it checked by a competent mechanic. Happy trails!

Koolponycar

OK guys, I have had about 3 or 4 audible sounds that sound like what the op describe as VALVE CHATTER on the RH side of my 5.0 My truck has 22k on it and it first done it during the winter January on 87 real gas, then about a week or so ago when very hot and humid on shell 87. Both times it did I had just refueled but not a complete fill up. This last time I had a new custom tune in for a week and put a $20 shot of shell 87 in as I was thinking of trying the 93 tune soon so didn't want a lot of gas to burn out to change tune. I returned to stock and it still did it 2 more times and I ran gas down to 30 miles to mt and refilled with shell 93. No more noise so far and runs great. Now I did have a K&N intake first time and now have a air aid jr intake with a AEM dry drop in filter and Borla stinger muffler. I have never seen any haze coming out of my exhaust and truck is not using oil between changes. So is it the gas or something more seriously?

Koolponycar

Truck still running great on 93 shell, going to top off as I am at almost 1/4 a tank. I may put a bottle of lucas through in with it. Thanks ncgator8 for that useful post, it helps make sense of what can be happening. I think mine is the low octane fuel and short trip driving that I do. About the time I get her warmed up going to work i am shutting her down, Im sure longer drives are better than multiple short trips, so 89 or higher for now on.

aiobst

So I finally fixed my rattling issue, always thought it was something like a heat shield rattling and it turns out it was. The heat shield on the passenger side behind the block isn't very big, kind of L shaped, and comes very close to the exhaust manifold/header? Anyways, couldn't get a wrench or ratchet in to tighten it and it didn't really feel loose, it's just thin and flimsy, so I bent it forward a little to put a bigger gap between it and the exhaust and voila, no more rattle. This is before you hit the catalytic converter on the way down the exhaust. Can easily see it laying on your back underneath the truck looking up at the right angle toward the direction of the wheel well. How this helps anyone else as I had tried different fuel routes and octaves with no luck do I didn't think it was a pinging issue in mine.

ncgator8

Right you are, Koolponycar. I had an '11 5.0 before this truck. It did not run well on 87- always wanting to downshift for power, kind of sluggish. I read the owner's manual, which stated that the engine was designed to run on 87, but that running premium would improve performance. Well, they were right about that. With 93 on board, the transmission stopped downshifting on a small incline (eastern NC), and mileage went up by at least 1 mpg- some justification for the added expense of the fuel. IMO, maybe they did not have all of the detuning figured from the Mustang Coyote. I do not know about the '12 model. By '13 (my current truck), the verbiage in the owner's manual had changed to run regular only. This model runs just about as well on regular as the '11 ran with 93.

Koolponycar

I loaded my 87 tune back in on the 27th, and topped off with some more 93 shell. But first I installed a 170 T-stat and removed the air aid CAI and custom heater hoses, engine cover and put the stock intake on with the AEM dry drop in filter. So far truck is running great. I will continue to monitor and if all is good eventually load my 93 tune. Never had a chance to try the 93 yet as I am very impressed with my 87 tune.

SkidogSemperFi

I'm with you, possibly bad gas for this guy. I run Shell most of the time or BP when I have to. Otherwise I drive past those Mom and Pops because of bad gas.