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Discussion Starter · #1 ·
So usually I feed my car 91 octane, for all of its 3k miles. Recently found out we can run 87 octane, so decided to give it a try to see what it would be like. And I swear the car is knocking. Can anyone tell me if it is? Here's a video I took while at idle:
 

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Best way to tell is to look through the accessport if you have one, all of our cars sound like a damn singer just a part of being direct injection if you are thinking that something might be wrong contact the dealer if still under warranty. If that's not the case check the things that would be easy to do, check oil levels, and even do a compression test if you have to. My car is noisy as hell as well.
 

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Discussion Starter · #3 ·
No accessport, only at 3k miles total so still under warranty. I swear I hear pings, but I'm not sure about it.
 

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Throw some Torco fuel in the tank with good fuel this should get rid of any false knock.
Half a bottle of Torco to a full tank of gas

From what I've heard on the vid, was just pulley sounds, If you have bad knock it should sound like a marble in a tin coffee can, that sound would indelicate a bad thing.
I'm probably wrong tho.
 

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Engines don't knock at idle, what you are hearing is the noisiness of our valve train and fuel pump. Totally normal. You will experience knock running 87 when you are accelerating hard, or under a load like going up a hill but engines do not knock unless under a load. Not to worry though, there are 2 knock sensors that will allow the ECM to quickly adjust timing to prevent continued knock events. As soon as the knock sensors hear knock, within milliseconds the ECM will take care of it. So no need to worry, you can safely run 87 octane on the stock tune.

Here is an article from one of the master tuners here on the forum that explains knock a lot better than I can.

Blog : Understanding knock and ignition corrections in your Ecoboost powered Ford : Stratified Automotive Controls
 

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Skip fuel additive, nothing positive for the motor. The sound is direct injection fuel pump, tend to have the diesel sound. Your car will be fine on 87 with factory tune
Our motors are quite loud....Direct injected engines are known to rattle. I mostly hear just the pump and pulleys.
However I wouldn't throw out the idea of Torco its fantastic fuel, adding this should get rid of any false knock the AP is throwing...although you don't have one.
 

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Our motors are quite loud....Direct injected engines are known to rattle. I mostly hear just the pump and pulleys.
However I wouldn't throw out the idea of Torco its fantastic fuel, adding this should get rid of any false knock the AP is throwing...although you don't have one.
False knock isn't from fuel issue...? Usually to stiff of motor mounts... no?
 

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False knock isn't from fuel issue...? Usually to stiff of motor mounts... no?
False knock can occur from hitting a reflector on the road, running over bumps while doing a pull etc. Loose motor mounts can allow the motor to torque and if the down pipe bangs against something it can cause false knock. False knock is when the knock sensors are triggered by noise other than ping and detonation.
 

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You're not wrong, motor mounts can cause false knock, even the down pipe can cause false knock.


Honestly I am just not fan of octane booster because I saw a lot of Terminators have issues and when motors came apart they tended to have residue speculated to be related to octane booster.

With that said it's probably fine when used reasonably. The motors i speak of were pushed to within a gnats eyelash of the edge... more power can be like becoming a drug addict, slippery fast slope to expensive problems! Lol
 

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False knock can occur from hitting a reflector on the road, running over bumps while doing a pull etc. Loose motor mounts can allow the motor to torque and if the down pipe bangs against something it can cause false knock. False knock is when the knock sensors are triggered by noise other than ping and detonation.
Yeah I was trying to say anything but fuel, so no additive
 

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When I first heard that sound just like in the video I rushed to the dealer thinking the car was going to explode. Because the car was so new in 2013 even the tech had no idea what the noise was. We had my car and 2 new ST's in the shop area all idling with the hoods up to see if they sounded the same. Myself, the tech and his boss were all standing there looking stupid trying to figure out the noise. The best part was one of the sales guys walked by and said " I didn't know those came in diesel " True story
 

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When I first heard that sound just like in the video I rushed to the dealer thinking the car was going to explode. Because the car was so new in 2013 even the tech had no idea what the noise was. We had my car and 2 new ST's in the shop area all idling with the hoods up to see if they sounded the same. Myself, the tech and his boss were all standing there looking stupid trying to figure out the noise. The best part was one of the sales guys walked by and said " I didn't know those came in diesel " True story
I also had almost the same experience! lol wow
 

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this is your injectors bro, if you were knocking at idle you'd need a new motor and you'd see a lot of blue smoke coming out of the exhaust
 

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Running higher octane fuel has always done mine right. You'll never have to worry about this problem running 92/93 on the factory tune.
 
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