Boomer01

I have started noticing a strange clinking sound coming from under the footwell or behind the CD/Nav when I lightly press the gas pedal. I can get it to happen often when coasting and tapping the gas pedal. It sounds like it could be some sort of metal linkage related to the accelerator, but I've also noticed the clicking sound when going over uneven roads like a driveway. It doesn't seem to be affecting anything, but it is annoying. Anyone had anything like this before?

daying

My 01 LS430 has exactly the same sound. Would appreciate any input. Cheers!

scottgolf

i would check transmission mount first. there is one that holds the tranny still. This is the place I would start, then have a look at the motor mounts.

I have an 05 and I am pretty sure these cars are drive by wire. I haven't really looked but I doubt they have any linkage on the peddle, On a high end car like this its going to be all computer controlled.

Boomer01

I had a shop check the mounts a week ago while in for something else. They said they were in good shape.

scottgolf

hmm., this is a stumper. I had an issue similar. I though oh crap I have a dash rattle and i thought it was coming out of the cup holder, and it turned out the ash tray just needed to be played with.

These cars are made so well and are so quiet that we notice little things a lot more I am learning.

Has the radio ever been out for repair? I used to work at a radio shop, and very possible it was not tighten or put in right.

Does the clicking sound sound like heavy pieces? does it sound like minor plastic pieces?

scottgolf

Could this be brake pads rattling? or maybe depending on the miles you have could it be bushing or endlink type parts. Such as on the swaybars so forth.

Just thinking alowed maybe somebody who knows can chime in on this. I don't know about the ls430 but I once had a honda that a bolt in the subrame that held it together was loose. I don't know how lexus is made, but I wouldn't think they would use bolts in such a high end car. I would think they would opt for more rigid construction, but I am just spitballing.

ancdmd

I've noticed a similar thing in the past few weeks on mine, sounds like a little bit of engine knock or pinging. Been using premium chevron with techron, so not sure what it is.

Boomer01

The radio hasn't ever been removed. I know it's not any plastic pieces squeaking. It is definitely a metal clinking sound. The reason I think it has to be some sort of a linkage is because I can get it to happen every time I tap on the gas pedal. I have also noticed the sound going over uneven or bumpy roads. It sounds like it is in the cabin, so I doubt it's the brakes.

ancdmd

I just now was at my mechanic getting a trans flush with Amsoil ATF and the trams mount replaced. I told my mechanic about the noise and he didn't know what it was. On my way home on the highway I just happened to be able to isolate the noise and was able to replicate it, it only occurs with the slightest depression of the gas pedal while coasting, around 50mph and higher. It really takes a continuous feather touch on the pedal to keep the noise constant. I went back to the shop and had the mechanic ride with me in the car, it took him a while to hear it but when he finally heard it he didn't know what it was. Our only guess was that it has to do with the air flow through the throttle body. I've never had mine cleaned on my '02 so maybe that could be the problem?

Boomer01

That is exactly the sound I am getting. I get it coasting at all speeds though. I did recently clean the throttle body. Hmmm. Could it be the butterfly valve?

At one point I thought it had something to do with the air vents, but that wouldn't be affected by the pedal.

ancdmd

Maybe something loose with the exhaust system...

ancdmd

I recorded the sound on a video and put it on YouTube, you can sporadically hear it throughout the video and it's really apparent from about 1:22-1:27 into the vid:

http://www.youtube.com/watch?v=fdS_l...e_gdata_player

caddyowner

I've had cars that made a similar sound and it turned out to be a vacuum hose leak.

Boomer01

Mine only makes a single clinking noise when you press on the pedal and sometimes one after you release it. It is not a constant noise.

ancdmd

For the most part it is a single noise since it is difficult to hold the gas pedal in a "sweet spot" to get the noise. Had the car at the Toyota dealer yesterday and the tech there could hear the noise too but didn't know what it was. He put it on the lift and couldn't see anything either, but suggested maybe it was something in the catalytic converter(s). I'd bet good money its the problematic heat shielding on that front exhaust Y-pipe.