Clunking noise when stopped and after shut off
 

I have an 08 AWD hybrid and just noticed this weekend that I hear a thumping/clunking noise when stopped AND after shutting the engine off.

The noise is a rhythmic clunk/thump that repeats a little more than once a second for up to 10 seconds before fading out after the engine has been shut off. It is more prevalent with a cold engine and becomes barely perceptible or not at all when warm.

I haven't been able to track it down to a specific location yet. Overall performance is normal. We did have some snow and freezing rain this week and the temperature has been all over the place - 50º during the day, 20º at night - so I'm taking that into account.

I was just wondering of anyone here might have any insight on this.

Thanks!

-todd.

Re: Clunking noise when stopped and after shut off
 

Are you hearing fuel tank slosh?

Re: Clunking noise when stopped and after shut off
 

You didn't say hissing, so I'm thinking that it's not the brakes depressurizing.

Re: Clunking noise when stopped and after shut off
 

I think it is probably normal. Is it the same noise you hear when you open the door? It could just be the system priming itself or shutting down. Could be the battery fan door in the rear opening/closing. Could be a number of things.

Re: Clunking noise when stopped and after shut off
 

Thanks for all of the replies.

It's a different noise than the usual start up and shut off brake and fan sounds.

I hadn't thought of fuel tank slosh... I'll see if it continues with this tank.

I just wanted to try to narrow it down and see if others have had similar issues first. I've already taken it to Ford twice for other noises and have learned that it's best to be as specific as possible with them. Of course noises tend to disappear when it's at the dealer, so maybe I'll drive past the service center and that will make the noises go away! :D

Thanks again,
Todd.

Re: Clunking noise when stopped and after shut off
 

My guess from your description is the fuel tank slosh personally. Its pretty noticable on this vehicle especially if you fold the back seats down.

Re: Clunking noise when stopped and after shut off
 

My 08 makes a similar noise, occurs with a full tank only, goes away at about 3/4 tank. There's a post about it somewhere in the forum. I thought is was a gas tank float valve, or something like that, in the tank, with inadequate clearance when the tank is full and it bangs around a bit. Had a similar noise in a Taurus once-- was told it was a fuel tank baffle that had come loose. Haven't checked with the dealer though-- let us know if you do.

Re: Clunking noise when stopped and after shut off
 

Well after taking my car in last week for some rattle in the brake pedal which took 5 days to fix, I think I'll hold off on this probable fuel tank slosh until the next oil change.

Thanks for all the tips...

-todd

Re: Clunking noise when stopped and after shut off
 

I filled up the fuel tank on my 07 today and am getting fuel slosh. I never noticed it before, but I may have just ignored it, since I recognize it readily.

Re: Clunking noise when stopped and after shut off
 

I hear a similar slosh/clunk noise at least once or twice a week in my 08 FEH. It has a recurrence or a pattern that decreases pretty quickly (usually within 20-30 seconds after turning the car off its gone), but it "feels" like a more solid impact from inside the car than liquid sloshing. I have tried turning off the car then getting out real quick to listen near the rear end of the car, but the sound has usually [almost] completely gone away by then. The frequency feels consistent with the fuel slosh idea mentioned above, but does anyone believe it might be a part or object in the fuel tank that is being tossed around? Or any other ideas?

Thanks!
-Andrew

Re: Clunking noise when stopped and after shut off
 

I hear the "clunking" sound and it is related to the brakes depressurizing.

This sometimes occurs ~5 min after the engine is shut off.

If you had the car in EV for 4.5 minutes prior to turning the key off, you could hear this 30 seconds after exiting the car, when normally you don't etc. This time is approximte. I've not actually measured it, and may vary a few minutes either direction.

My point is:
The brake depressurize is not always 5 minutes after turning the key off.
It is sometimes much sooner in my car.
-John

Re: Clunking noise when stopped and after shut off
 

I don't think they are describing the brake noise... they talk about a thunk that is repeated and gets softer over time... The brakes make a thunk or two and then quit. I'm pretty sure they are referring to the fuel in this case don't you think.

Re: Clunking noise when stopped and after shut off
 

I've noticed this noise. It happens when the tank is full or nearly so and is really noticeable at a stoplight in idle stop mode. It's more pronounced if you stop more quickly than normal.

I'm really familiar with the other noise. If you are still near the vehicle a few minutes after shutdown, there's a fairly obvious clunk - whir - hiss - clunk as the brake system depressurizes.

Re: Clunking noise when stopped and after shut off
 

I have it in my 08. I can also get the noise by rocking the car when it is sitting & the engine is off. The deler put in a new tank but no fix. THE NOISE WILL LAST FOR 40 SECONDS. will take it in next week.

Re: Clunking noise when stopped and after shut off
 

Fuel slosh is totally harmless. The danger of something else getting messed up when the tank is removed would make me tend to just ignore it. Mine does it, too, BTW.

Re: Clunking noise when stopped and after shut off
 

I ignore all these sounds too

Re: Clunking noise when stopped and after shut off
 

Its fuel sloshing in the tank... they can't "fix" it. The only reason its so evident is because your engine is off in EV and the car is so darn quiet in those times....

Just ignore it.

Re: Clunking noise when stopped and after shut off
 

Ditto here too. My 08 FEH makes the same sound when the fuel tank is near full. Harmless.

Re: Clunking noise when stopped and after shut off
 

Interesting. I have just recently noticed this sound, as well. The sound I am hearing is definitely, NOT fuel sloshing. This is a mechanical sound, not a liquid sound, almost like a heart beat. The volume of the sound stays steady for a while before it starts to fade out. The first time I heard it was after pulling into the garage very slowly in stealth mode. I walked all the way around the car but couldn't really tell where it was coming from, as it seemed just as loud near the front of the car as it did in the back. Somewhere underneath in the middle. It started fading out just before I was going to lie down on the garage floor and listen for it. I just figured it was some kind of pump (it sounds like an an old fashioned gas pump) and just one of the many odd hybrid sounds this car makes. Doesn't do it every time I stop, just once in a while. Mine is a 2008 4WD FEH.

Re: Clunking noise when stopped and after shut off
 

I think what you are hearing is caused by the fuel in the tank as it bounces off the front and rear walls of the tank.

Re: Clunking noise when stopped and after shut off
 

What is your fuel level when you hear it?

I thought it was something mechanical as well when I first heard it, then I realized that it was most noticeable after filling my tank and diminished until about 3/4 of a tank and after that it was inaudible.

Re: Clunking noise when stopped and after shut off
 

I've just recently noticed the sound so haven't yet seen a pattern. Listened for it yesterday when I pulled in the garage and didn't hear a thing with tank nearly full. I've heard tank slosh in this car and it is a very different sound, not as regular in beat and dies down much quicker. This is definitely a mechanical sound. That's why it caught my attention. I'll keep listening for it.