Please help - car makes strange noise when stopped and the engine is off

I drive a Subaru outback 2002/3 model (not exactly sure which, sorry). Before setting off on a long journey. I had my car serviced at the dealership. The clamps that hold the brakes on were rusted and therefore replaced.

Now I find myself 12 hours from home and the

car makes a very strange noise - almost like a quiet fog horn (if you can imagine such a thing). The strange thing is itdoes this after I have fully stopped the car, turned it off and removed the key. It doesn’t do this every time, but when I last stopped the noise continued for 30 seconds or so.

The next time you hear the noise, get out and remove the gas cap. If the noise stops, it’s the EVAP system for the gas tank making noise. And unless the Check Engine light comes on with a code related to the EVAP system, there’s not much that can be done.

Tester

Thanks tester, I’ll try that in the morning. No check engine light has come on yet. The noise seems to be coming fromthe right front of the car.

The EVAP system has hoses that run from the gas tank to the engine. So try the gas cap removal test to see if it has an effect.

Tester

Could it be your radiator fan running?

I don’t think it is the radiator - pretty sure I would recognize that sound. It also sometimes happens- for much shorter periods- when I slow down/stop at a light. It doesn’t seem to berelated to applying the brakes. I also tried drink in 3rd for while (automatic transmission) and pressing the front of the car up and down to see if it related to suspension. Neither made a difference.
I’m an hour or two from the nearest dealer. And need to head home -12 hr drive - on Wednesday. Any suggestions are greatly appreciated.

If all the fluid levels are good and no warning lights are on, drive it home.

I doubt the noise has anything to do with the recent brake work.

Could the noise be coming from under the dashboard? The HVAC system, perhaps?

As the car was just serviced I’m pretty sure the fluids levels are ok. No warning light are on. I’ll check underneath the car for any leaks.
Thanks again for all your help and advice. I really, really appreciate it.

“As the car was just serviced I’m pretty sure the fluids levels are ok.”

It would be nice to be able to assume that all fluids are at the correct level, but that assumption could be fatally flawed!

Mistakes can happen when servicing a car, and it is entirely possible for the level of your motor oil or your transmission fluid to be either too low or too high. Even though neither situation is likely to be the source of this mysterious noise, I strongly suggest that you check those fluids. It is also a good idea to eyeball the brake master cylinder and the power steering reservoir, and to check the dipstick for the front differential.

I make it a rule to check my fluids right after the car is serviced. Normally, everything is fine. However, once I did find that the oil was grossly overfilled, which can be as bad for an engine as underfilling with oil.

When I took the car back, the service manager admitted that the very old meter used to control oil flow from their bulk tank had been “flukey” recently. They drained the oil, refilled it, and we both checked the dipstick for accuracy.

And, on my next visit, the service manager showed me the new digital meter that they had obtained for metering oil flow. Even though there have not been any subsequent mistakes, I still check my fluids immediately after the car is serviced.

Incidentally, you can clear up your confusion regarding the exact model year of the car that you are driving.
Just open your wallet, take out the vehicle registration, and see what model year is listed on the registration!
It doesn’t get much easier than that.

Checking the fluid levels was really good advice. The coolant reservoir was low so I filled that. The noise now seems to have stopped. The good news is that I made it home in a straight shot with no problems.
Thanks again to all of you for sharing your wisdom. I’m now inspired to look for a basic car maintenance course.

In addition to looking for a basic car maintenance course, you need to continue to monitor the coolant level very carefully, as there is either an external leak or a head gasket problem. Just as you assumed that fluid levels were correct when the car left the shop after its recent servicing, I think you are assuming that all is now well with your car after replenishing the coolant. That would be nice, but it is not realistic.

Coolant levels remain constant unless there is an external leak or a head gasket problem. In fact, the existence of head gasket issues with this engine make me suspicious that your engine is consuming coolant as a result of a breached head gasket. If you don’t keep a careful eye on this situation, you could be driving your car to an early grave.

Again, good advice. I took it back to the dealer today and had them check the caskets and cooling system. They said everything was ok but I will check the coolant level each morning before I drive.