sushistrip

I cannot find any information on this subject. Are the knock sensors underneath the intake manifold in the V? I have an obd2 bluetooth device that lets me log pids but there is no pid for the knock sensors, however this could just be the device not picking them up.

Car has heads/cam. I'm getting what I think is detonation at 50%-100% throttle in 2nd and 3rd gear. Fairly distinct sand in a can type of sound. It goes away pretty quickly, within 1-1.5 seconds. I've never heard detonation before, so it possible this is just exhaust related, although it's completely stock exhaust. No codes or CEL.

Any advice is appreciated, thanks!

edmundu

Knock sensors on Gen IV's are located below header's on each side of block.

Not device, but software not reading the knock sensor data...Might want to check if they have custom pid setup available...

When was it tuned?
Has the car been sitting, and perhaps has old or winter blend gas?

Try running out the current fuel and get fresh fuel and see what happens.

sushistrip

Ive ran a couple tanks of 91 through it at this point, but before I bought it the dealer only put about a thousand miles on it over a year period.

Has 28k miles, was probably tuned around 23k miles when the previous owner did heads and cam.

I'm going to get it retuned for peace of mind, just trying to do my due diligence before I take it to them.

There are some custom pids I can use, but I was curious as to why it wasnt showing up on the standard list.

Unreal

Knock Retard is the PID you monitor for knock.

As said above, sensors are on side of block on gen 4/5, gen 3 they are in the valley.

sushistrip

What kind of value do the knock sensors report? Is it like a knock frequency or amount of timing retard?

Unreal

Degrees of retard

sushistrip

Thanks guy! I'm starting to think that this sand in a can sound is coming from my cats... It is not a rhythmic sound at all. It's very intermittent and only when under heavy load, so above 3k rpm and more than 80% throttle. Sound is directly below and a little in front of where the shifter is. Audible with the windows up and I can also hear it outside the car if I have the windows down while doing a pull. This sound doesn't happen ANY other time while driving the car.

sushistrip

Sooo...coins in the cup holder...

Removed coins...no more sound. Put the coins back...sound comes back...
I thought I had checked this when I was diagnosing the sound, apparently I didn't though lol.

rjacobs

I would NEVER have admitted that...

"uh yea, was a loose kanuder valve spring keeper, took some ball bearings and 30 weight oil to fix"....

sushistrip

As much as I would have loved needing to replace the mid-pipe for like 700 bucks, I'm relieved it was something silly lol.