Rennwagen

Do any of you hear a clunk coming from under the car (sounds like the fron wheels) when you first get under way?

This car makes so many noises that no other car seems to.

Perhaps I'll just take the same route I did with my most recent Moto Guzzi - make the enhaust loud enough that you can't hear anything esle!

Spin9k

'Clunk' is normal. Remember, 'Search' is your friend here.

Rennwagen

Good to know that we have the search ***** on this board too. :D

I've been looking and reading. I'm not new to this car tuning thing, just the rotary thing. This car seems to have all kinds of quirks and the misinformation and hysteria that is on this site can be staggering. I'm just trying to cut through it all.

Thanks.

goforwand

Don't be so harsh Rennwagen.....just the simple phrase "clunk" yeilds 2 full pages of threads that would answer your question!

Not trying to bust your *****, but there is so much relevant info on this board, that sometimes the most banal of inquires will lead to all your answers.

Welcome aboard, and the search function really is your friend :D

Gheist

"Clunk" is the antilock braking testing. Or so I've been told on this board. The dealer also told me it's normal.

I hate searching through hundreds of threads.

I know, I know, people should look first.

RXE16T

ABS self test, totally normal.

Rennwagen

Thanks all.

I didn't think I was being harsh. I've been searching and reading this board for about a week. There is some good information, but it requires sifting though a lot of, "OMG chrome wheels ownz joo" threads. :D

Tony Orlando

Ha ha! So true.... Ricers abound on this forum. And those that can't type the English language.

I'm sure you'll get sick of reading, "OMG, thats teh shiznit, he was teh pwned!!"

Hard to find good info sometimes.

rotten42

Hey, I have that clunk too...good to know that its nothing to worry about.

snap-on

You better have the sound or the ABS light would come on.

Rennwagen

So what exactly is happeneing with that clunk. Yes it is an ABS diag function, but what is the car doing? Appliying the brakes? Sending a signal to the ABS sensor that the wheels are moving and the sensor then trips the ABS once to make sure it works? Sounds good, but does anyone know?

I've never heard this before on any of the other (6) ABS-equipped cars I've owned.

snap-on

CLICKING / HUMMING OR BUZZING NOISE
Applicable Models
Model Starting S/N Ending S/N
2004 RX8 00000000 ZZZZZZZZ

A clicking / humming / buzzing noise may be heard as vehicle begins to move from a stop, shortly after starting engine. The noise duration is typically 3 seconds in length N only occurs once after starting the engine. This noise is most likely coming from the ABS /DSC hydraulic unit as it performs it's self test.

Spin9k

Nope, wrong noise. 'clunk' really does summarize it... no buzzing, humming, or clicking about it. Try backing out of a driveway... you start ... then 'CAA-LUNK' sort of like a 10 lb plunger ca-lumping into a can. :D

snap-on

Let me look again..sec

Thats all the MRI's/TSB's I see listed...

Maybe "POP" and "CLUNK" isn't in the verbage?

Rennwagen

I get that it is the ABS system performing it's test, but what exactly is that test and whay does it clunk. Something needs to move to get a clunk. What is the ABS system moving in order to "test" itself and why is this different from every other car I've ever driven?

wankel8

Yea, I have the "clunk", too. Most noticable after backing up, then the clunk happens when I start going forward. I expected it to be the differential... my friend who owns an automatic transmission shop heard it the other night and he agreed with my diagnosis. He didn't seem to think it was anything to worry about. BTW, don't slam me, but I do have an automatic.

Genesis

Same here Wankel8....when I park at home (a tight space). Pull in nose first, slight back up, then into 1st, small move forward and hear the clunk. Doesn't impact the forward motion at all, just the noise. Interestingly, only happens when the car has been driven for a while and is fully warmed up, else when it's relatively cold, don't hear it. Perhaps this is related to the ABS issue, but the sound comes from the rear, so I'm leaning towards the explanation having to do with the rear differential. After reading all the posts here, not worried about it, but thought somebody might know exactly why the clunk is present.

Rennwagen

So far, people say it is normal, but no one can exlplain what is going on.

wankel8

Interesting, Genesis... my clunk is not temperature dependent. In fact, I notice it most when I just leave home... car has just been started.

Rennwagen- my educated guess is that we are hearing "slop" or "free play" in the differential. A good analogy might be a old bicycle where you "pedal" backwards to put on the brakes. Once you start pedalling forwards again, you have to take slack out of the chain and the guts in the rear hub have to "grab" before you start going forward again. Hope that helps (and makes sense).

ChrisP

The clunk on mine is once the car reaches 3/4 KPH either forward or reverse, in gear or not, the first time you move off after starting.

Because my driveway slopes reasonably, I have been able to experience the clunk in neutral with my foot on the brake pedal. With the clunk came a slight kick back on the brake pedal. And no, I have no idea what it's doing. None of my other ABS equipped vehicles ever did this.

snizzle

here's another vote for the clunk! yay clunk!

who else wouldn't have it any other way?!?!?!?

zoom44

if you READ THE MANUAL you wouldnt have to have the board tell you and still be unconvinced ("or so i have been told), you would know.

not just gheist but the rest of you too. the clunk is the abs self test. it happens after you start the car and go ver 3-4 mph. whether you go forward or backwards. everytime. the brakes are pumped by the abs. thats all.

a clunk that is temp related and happens after you drive is completely different.

Jarred

I get a clunk just throwing it into first when the car isn't moving at all.

Rennwagen

WE have an answer becuase of this man's driveway. I'm assuming that you're rolling down with your foot on the pedal. You then get above the, "testing speed" and activate the test. You feel the feedback through the pedal.

If there is feedback in the brake pedal, what is happening is that the ABS sytem is, "tripping" itself and releasing pressure on the brakes as if there was slippage. It is going through a scenario where the ABS system needs to activate itself and it actually tests that function. Interesting.

That is an explanation that makes sense.

The explanation that there was, "play" in the diff doesn't. There should be no, "play" anywhere in our drive systems. The bike freewheel analogy doesn't fit.

Rennwagen

Calm down Zoom. the manual (nor anyone on this board) has been able to explain what is actually going on. Yes, the ABS is testing itself. Ok fine. What EXACTLY is it doing (finally answered above)? WHY does it do that (still unanswered)? WHY is this ABS system different from every other car I (and many others have owned)?

For a lot of us, the manual and the dealer's telling us that, "it is normal" isn't good enough. It is because of that that I know all that I do about cars (which is a lot).