Hey guys, i get a knock of about 93 when i am high RPM's when WOT. Should this number be something to be alarmed about.

Mods:
intake
dp
mp
HKS Super Dragger 3' cat back
PFC

 

Every car is different, no two are alike. While you may have 93 knock it may or may not be true knock. This is something you need to figure out. The knock sensor will pickup noise caused by miscellaneous things such as having a drive train slack, parts hitting or scrapping against each other, etc. Things such as these will cause knock to show up under low or cruising speeds and light acceleration. If this is not the case then odds are that you do have true knock. Also, look for major spikes, while going WOT, you'll notice that there's a certain level of knock (or noise) and if you all of a sudden see a major spike that is way out of the average, then chances are that's a true knock.

First thing is first, you need to find out how much of it is just noise. From that, you can figure out if it's a knock or not.

 

I notice you have a midpipe.... how is your boost? And are you tuned for the additional boost you will most likely be running over stock?

are you creeping?

 

thanks guys, i am not creeping boost, my Cat back is actually quite restrictive, and keeps the creep to nill.

I believe it is knock, because it does spike from about 45 to 93, and its always 93.

But is 93 a excessive amount? I need a Fuel pump soon, just so i can rule that out.

 

Does it do it under throttle?? Or does it do right when you let off?? If it is just when you let off that is normal. If you are watching it and it does it under WOT and normal knock is 45, I would check my AFR's to start with.

 

I wonder if it is possible to characterize a car's knock "background noise" by recording the knock readings during deceleration, when the injector duty cycle goes to zero (on my wideband, it says "AIR" at these times, because absolutely no fuel is running through the engine). No fuel means there can't be any real knock, yet I can still get a knock reading of 50 or so depending upon the RPM.

Finding and subtracting out this background reading from the actual reading might provide a value that would remain more constant from car to car.

 

can an engine still be seeing real knock under wot full boost pulls if the a/f ratio are good and safe (10.5)?

 

Even with rich AFRs, too much timing or too high a boost can cause knock.