Knock/valve slap/crick noise under accel
 

:iono: Not sure what to call the noise but i thought it was tune related and it seems it isn't This noise i came to hear it right after flashing my car, took the car for a spin and while rev matching for a downshift i heard it. I parked the car and gave the gas pedal a few kicks to replicate the sound and there it was, sounds like knocking due to bad gas, bit its not. I'm not sure what to call it, i dont have a CEL light or any mods in my car except the flash, i flashed back to stock tune and still does it. If anyone else has this and may know how to fix or has taken it to the dealer to check it, please let us know.
[ame="http://www.youtube.com/watch?v=4FTo_kKjVMg"]Frs knock noise - YouTube[/ame]

I have had this EXACT same sound since about 1500 miles, now at 10k.
Asked around to a few local guys and they all thought I was nuts so let it go.

So ya, zero idea what it is but I have the exact same sound forever but it was not there when brand new.

any mods?

Lowered, that is all.

I think mine is making a similar noise. I hear it most often when shifting up to 2nd or 3rd but, I can also sometimes get it to do it by just punching the gas without shifting. I have tried to replicate the noise with someone in the car to see what they think. It just doesn't do it with a passenger or does it much less loudly and is too subtle for someone else to really notice (which it weird). I definitely notice more when I drive alone. I have not tried to replicate by just revving it in neutral like in this video. I'm going to try tomorrow.

I know i said this in another thread but i have this issue too. I thought it was only me but now i see other people have this issue too. Curious to see how many others have this problem. For those that have had the cel and car was repaired, did you have this noise? Did it disappear after it was repaired?

I switched back to stock map and the noise went away 90% but it was still there some times. The second I flashed with the latest racerom, the noise was back. Seems to me like a valve knock or something that like that. It happens to me only when free revving and not under load, while shifting quick and hard , the sudden press of the gas causes it.

For me it happens stock or tune and there is no difference between em. Not sure what it is.

John said he was going to take a look at the logs and see if he could do something about it. Hopefully he could aid the saituation.

Sounds like intake noise to me ... Mine does the same 100% stock

O/T: That's some pretty crickets you got there under your hood.

lol yeah the crickets get pissed off every now and then and start a riot.

I have this same sound. I have to agree that it sounds like an intake/TB noise. It's weird but doesn't sound harmful.

Agree on the intake/throttlebody noise. Maybe some turbulence when the valve is almost closed and high vacuum?

Same sound here. A/T FR-S.

I really dont know, to me it sounds like something with the fuel and the tune. I could be far from the truth but since it does it when its running the latest tune and not while stock im leaning towards the tune. I dont really think a mechanical condition would show up with a tune but then again it might if the fuel and timing are off. Do you guys getting this noise, all have tunes?

I currently have the FA20 stg2 tune flashed and am not experiencing it. Hmmm. May flash back to my stock and visconti roms tonight to see if it reappears.

Except the cricket I fail to hear anything wrong. Just the sound of the butterfly valve opening / closing.

i said this yesterday but i agree that its something with the intake/tb. Also agree with the butterfly valve opening/closing but its def not normal because one of my friends has an frs fairly new (600miles) and i cannot replicate the noise on his car. I feel like its getting stuck or something.. Its alot louder than the video posted for me. Ive already brought this up to toyota/scion and the tech took the car for the drive admitted he heard the sound and his response was"all 6spd trannys make that noise" Dude was talking out his (_l_)

lmao, for real man. When you go to dealers you need to be ready to listen to all sorts of retards like those and get ready incase they keep on pretending they dont hear anything. Lawyers are your friend, sometimes, before getting to that maybe calling toyota or someone else that could do something about it.

There is nothing wrong with that noise. If that video is exactly how it sounds in real life and I was a mechanic, I would think there's nothing wrong with that.

People are paranoid.

I don't know but i dont think any car is supposed to make that noise when reving it. It only happens when applying the throttle sharply and also it doesn't happen 100% of the times, or with a stock tune. If it were normal i would imagine it happened all the time.

did you have a cel/sl issue?

Wait, so you're not a mechanic?

Not saying its a serious issue because ive been driving around like that for 3000+ miles but i dont think its normal. It didnt sound like that when i first got my car...ive heard my share of frs/brz and none of them had that noise. It sounds like rasp in a way. When your in the car its alot louder. Its to the point where people sit in my car and say what is that noise. I can actually remember one day that visconti was in my car and gave me that look like what is that noise and told him it was nothing because i felt it was nothing. Not sure if he remembers tho...i dont think its anything serious tho and it just may be normal.

Not by trade:respekt:

Well we wont know until something goes wrong with the car or maybe John comes around with a tune refined and makes this go away. Only time will tell. I'll keep the thread posted, i have ticket open and waiting for john. I tried to replicate the sound with the hood open, listening near the TB/manifold area and it does come from there but i took off the intake tube and play with the butterfly and it doesn't make that noise in any position or throughout and range of motion.

Only other thing I can think of is that this car is drive by wire so it could be the throttle solenoid making the noise?

Anybody have a mechanics stethoscope? Sounds like it's time for some probin and listenin..................

What cnk said could be a possibility, i may try and use one of those at school and see if i could pin point the noise. The odd thing, again, is that it has something to do with the tune at least in my case. Maybe the throttle activity is adjusted or incremented, made more sensitive... somethings gotta be it.

In my experience it is definitely tune related. I know i had this noise on an older visconti flash, i'm currently running fa20club stg2 flash and do not have the noise. Once I find some time I'll switch back to the visconti flash and stock to see if the noise returns.

exh valves

I recall the first tune i had which was done locally didn't have that noise at all, then I switched and immediately heard it at my frost downshift. Hopefully John could do something about it.

Use a long screw driver, it works great for a stethoscope. :)

That long screw driver trick works
I've tried it at school. I was in my way home tonight on map1 which is tune plus stock rev limiter and the noise was pretty much gone, the second I switch to map3, there it was again. I sit think the rev limit has anything to do but once again this confirms something with a map.

Sounds like detonation/knock to me from running too lean. The knock sensor will pick up the knock noise and retard the timing, but you will still hear it for a split second before it retards. I have the same issue with my car in between shifts. I've built many motors/cars for track over the years, most of them turbo, and it sounds exactly like detonation. That's why when you put the other flash back on there, it mostly eliminated it because it's most likely running richer with that tune. I don't think it's intake noise, because it should make that noise regardless of what tune you have in the ecu. You said it does it with the new flash/tune. These motors are very high compression from factory, and mixed with crappy 91 octane and a lean tune could create a condition for detonation/knock. I would be concerned, as it could do serious damage, like melt a piston, crack a piston ring, etc. I would firstly get your HPFP (high pressure fuel pump) replaced at the dealer under warranty to fix the cricket chirping, because you never know if that has anything to do with the lean condition too, it shouldn't, but I've seen some strange things with these cars. Have them put the lastest flash on there too, and if the mechanic at the dealer says the noise is "normal", go to a different dealer.

You think our engine can suffer from knock/pre-ignition at idle?

It is quite unusual for detonation to occur when just free-revving (no load), but I have seen it before in the past with other cars that were excessively lean at low throttle conditions. Another factor is the VVTi. These motors have proven to have issues with the cam gears, and if a cam gear is out of calibration, it could be advancing or retarding the cam too much at certain throttle inputs. The flash can also affect the VVTi.

Definitely have this same issue on my brz. Usually happens in the freeway without any shifting and sharp presses of the gas.

Plug/remove the sound tube. It made a difference in the ticking noise in my cabin.

If it doesn't help, you can always undo it.