positive knock at WOT

[BMill705]

You're reading what I am saying incorrectly,
I never said the knock sensors are reading air escaping the exhaust lol. An exhaust leak can cause a ticking sound that in some instances may be picked up by the knock sensors as audible knock.

I stand by my statement that air simply escaping the system does not cause knock. Now if you have loose/damaged exhaust that is rattling/banging/etc, the knock sensors will pick that up. The knock sensors have no idea where air is going, doesn't matter if it's escaping through a leak or out the back of the exhaust.

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[codemanstang]

Throw some octane booster in it and see if the knock goes away. If it does, you have actual knock. If not, you have false knock.

So I kinda tried that lol and didn't fully realize I needed the tube from the trunk. So I lost probably 1/2 the bottle. Once I put the tube in it went down. Filled full tank of 91 still knock. There is exhaust leak but it's kinda small and no loose rattling clamps.

 

[BMill705]

Don't worry man, as long as you're not out racing at wot all day you're fine until lund gets a chance to look at your logs. They are great tuners and will advise you what to do next. Just seeing positive knock doest tell you the whole story as it can be a number of things causing it. Some of us just have bad gas in our areas so try a few different stations and see if anything changes. What octane booster are you using? I normally add a can of octanium to a half tank of gas which is what lund recommended.
Here's a little knowledge for the guys in here thinking it's so bad to drive it with knock, enjoy.:cheers:

So I kinda tried that lol and didn't fully realize I needed the tube from the trunk. So I lost probably 1/2 the bottle. Once I put the tube in it went down. Filled full tank of 91 still knock. There is exhaust leak but it's kinda small and no loose rattling clamps.

 

[codemanstang]

Don't worry man, as long as you're not out racing at wot all day you're fine until lund gets a chance to look at your logs. They are great tuners and will advise you what to do next. Just seeing positive knock doest tell you the whole story as it can be a number of things causing it. Some of us just have bad gas in our areas so try a few different stations and see if anything changes. What octane booster are you using? I normally add a can of octanium to a half tank of gas which is what lund recommended.
Here's a little knowledge for the guys in here thinking it's so bad to drive it with knock, enjoy.:cheers:

hey good vid man thanks. I almost forgot about that guy from VMP he has some really informative vids. Did some WOT pulls tonight and i did see less knock so idk, but i guess Lund will give me some info tomorrow and i feel better about driving it overall. Its pretty sweet getting to know more about the car then i have before, ill update with what Lund suggests

 

[codemanstang]

Lund is suggesting probably bad gas. I get up to 4-5 knock, and they say it looks almost like 87 octane. Going to try the octane booster again this time not spilling it all over the place lol

 

[BMill705]

Try to find a station that stays busy.
After comparing all my logs with different stations in my area I actually found that walmart/Murphy worked best for me. Goodluck man.

Lund is suggesting probably bad gas. I get up to 4-5 knock, and they say it looks almost like 87 octane. Going to try the octane booster again this time not spilling it all over the place lol

 

[gqneon]

I've had false knock issues on both my blown 2015 Mustang GT's. I've also had crappy gas times where minor real knock sensor activity was visible. Torco or your favorite additive for octane on back to back logs (once mixed) on the same tank of gas will answer that question pretty easily.

I had a vibrating stock mesh flex pipe section on that passenger side manifold (stock manifolds to resonator) on both cars and I just replaced it with long tubes this week - rattle gone, slightly less knock sensor activity. IF everything isn't as it's supposed to be, even a loose bolt or something rubbing or a pipe edge (like the header or midpipe) making brief contact with something on engine torque over can drive you mad chasing down false knock stuff. Good luck and please post if you find the source!

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