I was pissing around with the hood open today and the car was running and sounded like something was rattling against something, so i look around everywhere and dont see anything moving but i can hear 2 things hitting and it was coming and going from what sounded like inside the engine, so i put 2 and 2 together and assume i was knocking, because oil was good, nothing coming out of the dipstick, and the only thing that changed recently is i am down to a quarter tank of 93 gas with a 15oz can of B12 Chemtrol Fuel system cleaner that said if less than 15 gallons mix it 1oz:1 gallon and instead of trying to leaving out 1.5 oz i just put the whole can in....the ingredients included xylene, methanol, isopropyl alcohol , and i believe toluene ...so the question at hand is could this be causing knock...i am not getting and CEL from a misfire or anything...discuss

 

injector cleaner increases the temperature to burn off all that **** in your engine.


my car felt like a dog when i put a bottle in..



wasted through that tank.. filled it back up again with 93.. felt much stronger.

 

It wouldn't knock at idle.

My valvetrain is loud like that too.

 

alright so when this tank goes down and i refill it should go away

 

hypothetically yes....

i didnt hear any knocking, but all cars are different

 

not just noise but a *tonk**tonk* sound that moved all around the engine [stayed mostly to the passenger side] overtop of all the other noise

 

i thought knocking sounded like a *ping*, also, like stated, knocking wouldn't really happen at idle, a loud vavletrain or just uneven rough idling from performance mods could be a cause. My car makes some clackity clack clack sounds when its cold out.

 

I think a lot of our cars do that. It kinda sounds like a marble in a spray paint can.

 

i have had a similar experience....was getting some throttle hesitation at mid-rpms, figured fuel system may be dirty, so threw in a bottle of STP injector cleaner. My hesitation issues got SIGNIFICANTLY worse. I would wind up second or third gear through ~3-4k rpm, then the car would just STOP accelerating like I hit the brakes, throwing me forward in the seat against my belt!!! So anyway, I ran through the tank, filled w/ 91 gas only and problem has since been alleviated. (Although I still get some hesitation...I think it's time for fuel filter replacement)

 

knock is very rarely something you will hear.
and it certainly doesnt sound like the word itself suggests.
and would be EXTREMELY rare at idle.

 

well burned that tank of filled up with BP 93 and the noise is gone now

 

i've had that knocking noise. i had this crazy idea that it was my heat shield or something. sounds more toward the passenger side, and toward the front of the motor. hasn't affected performance at all.