Clunking / knocking sound after engine start

Daskid · Jun 11, 2009, 11:38 PM

So I got my week old X and everytime I warm it up for 1-2 mins before driving, I hear a couple knocking sounds while still parked and I'm not doing anything, just listening to the sound. I sounds like it's coming from the engine bay.

For the record, I'm still in the break-in period and has 277 miles on the odo. I never shifted past 4k and never launched the car and burn the clutch!

Any thoughts?

flyguycfi · Jun 11, 2009, 11:53 PM

Like when you turn the AC on and hear that click?

Daskid · Jun 12, 2009, 12:04 AM

Quote:

Originally Posted by flyguycfi

Like when you turn the AC on and hear that click?

Oh that click I'm aware of. I hear that in every car that I have.

I'm literally sitting in my car doing nothing and waiting for the right idling/temperature for the engine, then all of a sudden... "clunk"....then after 5-10 secs "cluoink" again.

Do you guys think it's the turbo? Or maybe the intercooler? Definitely not the A/C.

Good try though!

EngRWW33 · Jun 12, 2009, 05:56 AM

open the hood and wait for said "clunk". See if anything stands out or if you can get a better idea on location of the problem.

empirepb210 · Jun 12, 2009, 08:53 AM

mine used to clunk immediately after i turned the wheel to reverse out of my driveway.
It would go, clunk...clunk.. but now it went away.

fredzy · Jun 12, 2009, 09:14 AM

Maybe you accidentally filled up with regular gas? Or maybe you got bad gas from an older pumping station or something. Either of those could give you some engine knock.

Daskid · Jun 12, 2009, 09:52 AM

Quote:

Originally Posted by EngRWW33

open the hood and wait for said "clunk". See if anything stands out or if you can get a better idea on location of the problem.

It's really a faint clunk sound when I hear it. I'll try and listen to it from the engine bay later. I'll try to do that later after work. Thanks!

Quote:

Originally Posted by fredzy

Maybe you accidentally filled up with regular gas? Or maybe you got bad gas from an older pumping station or something. Either of those could give you some engine knock.

I recently filled up with 91 octane rating gas at a Chevron station here in California. But before that, the dealer filled it up about 90% of the tank. Who knows if they put 91 octane rating or 87.....

scottatyamaha · Jun 12, 2009, 10:38 AM

I know if I bought a car that had been sitting on a lot for almost two years I would check and change the oil

EVOXTIMES · Jun 12, 2009, 10:41 AM

I know exactly what clunk your talking about.......I have never really investigated exactly what it is .....but......i have a sneaky feeling that its a belt tensioner clunking a little after the belt tightens up.......my noise always seems to happen after i start moving.......so i imagine after its been idling....and you put it in gear and then the engine moves and tightens the belt tensioner to clunk it for the final time.........and then i dont really hear it......like i said.....just a theory...i hear it almost ever time is start the car and start moving.....hope this helps

**macPSU** · Jun 12, 2009, 11:15 AM

I get a knocking sort of sound while my car is warming up, but it's from the exhaust. It's more of a popping sound, like small backfires or something. It's definitely the exhaust from what I can tell, there's no noise in the engine bay.

Not sure what yours could be though, pop the hood and try to single out which part of the engine compartment or motor it's coming from.

axtran · Jun 12, 2009, 11:18 AM

Dealers usually fill your car up with 87. South Coast Mitsu here in SoCal gave me a credit to bring to a Shell station to make sure I get that 91 good stuff in the car.

wild01ride · Jun 12, 2009, 01:33 PM

Quote:

Originally Posted by Daskid

So I got my week old X and everytime I warm it up for 1-2 mins before driving, I hear a couple knocking sounds while still parked and I'm not doing anything, just listening to the sound. I sounds like it's coming from the engine bay.

For the record, I'm still in the break-in period and has 277 miles on the odo. I never shifted past 4k and never launched the car and burn the clutch!

Any thoughts?

Do you have a GSR or an MR?

The MR's have a significant amount of "clunking" just after engine start - it's something like the clutches learning their pre-feel position and partially engaging the SST input shafts.

Also, there is a "rattle" sound that occurs at idle, especially with the car in neutral or park.

If it's a GSR...???

All in all, the Evo (as in the past models) has a pretty unstable idle with some popping and whatnot as others have mentioned.

If you get any more info, make sure you let us know what you find!

lhsa · Jun 12, 2009, 03:03 PM

definitely change the oil and run 2 tanks of gas through and see if it repeats

Daskid · Jun 12, 2009, 08:34 PM

That's weird... I don't hear the sound anymore. I swear it was there yesterday. I only here the starter clicking like 4 times when you turn the ignition to the "ON" position, then I hear an audible "tick" after 2 secs when the light from the gauge cluster turns off, then I hear a faint "tick" then the info screen shows the miles I have left for the amount of gas that I have. Then when I actually start the car, put my head in the engine bay, listening for it, I hear no "clunk". Only the sound of the engine running.

I also checked the oil and it's about 1/32" below the upper hole of the dipstick. It looks clean, like a transparent yellowish color. I have a GSR. Maybe it got fixed somehow? I'll change my oil when I reach 1,000 miles.

I'll still try to listen for that sound. Anybody experiencing a similar situation? Thanks for all your input guys!

tipoytm · Jun 12, 2009, 08:54 PM

the best way to find out if this is actually coming from the engine is to pop the hood. have your wife start the car, put it in neutral, and have her rev it up. then you stand in front of the engine bay and listen carefully... should be easy to pinpoint where it is coming from.