Knock/valve slap/crick noise under accel

[White64Goat]

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

[yomny]

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.

[xjohnx]

Originally Posted by yomny

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.

[gmookher]

exh valves

[yomny]

Originally Posted by xjohnx

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.

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.

[Surakusa]

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

[yomny]

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.

[Mark Slide Squad]

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.

[Rayme]

Originally Posted by Mark Slide Squad

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?

[Mark Slide Squad]

Originally Posted by ottopilot

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.

[Pake1]

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

[maj75]

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.

[Gen]

Several of us noticed the same sound after installing the Crawford AOS.

[fistpoint]

Originally Posted by brichard0625

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"

You could own every dollar in the world placing bets on dealerships either not hearing the noise you brought the vehicle in for, or they do hear it and insist it is both normal and they all do it.

The new Genesis Coupe forums for example are ripe with posts about their noisy wastegate rattling. Same responses from their dealerships, "the noise is normal, they all do it". They've gone to making jokes about having a friend drive up with them next time in their "non rattling" GC and asking the tech to use a hammer so that his sounds normal by having a rattle put in.

Keep insisting, go over their heads if necessary, call corporate, try another dealer...multiple choices.