Compressor/pump noise when car is off

[Zardoman]

Hi guys,
this is the second time that I've noticed that my car started making some weird noises from the "bottom" of the car, it sounds like a compressor or some kind of pump, it went on for about 5 mins as I walked around the car, opening the hood and trying to figure out where it is coming from..


The noise is most clear when I put my head under the rear diffuser, im guessing its a component between middle of the car to the trunk, because I couldn't hear it when I open the trunk.


P.S. This started about 4-5 hrs AFTER I shut off the car.


I have also on a few occasions had a "long" ignition for the car to turn over, I have the pushstart feature on my limited BRZ.


I wonder if anyone have this issue, I will call Subaru to check this as well.


appreciate all the comments.


thanks!

[mav1178]

Please read the owner's manual.

-alex

[Zardoman]

so I'm guessing this is normal from the less than helpful comment?

[mav1178]

Less than helpful? Yes.

Here, let me find it for you:
http://techinfo.subaru.com/proxy/712...316DSTIS_2.pdf

Noise from under vehicle after turning off the engine
Approximately five hours after the engine is turned off, you may hear sound
coming from under the vehicle for several minutes. This is the sound of a fuel
evaporation leakage check and, it does not indicate a malfunction.

More helpful? Yes. But it is mind-boggling that the owner's manual is not read more often by owners of the car.

-alex

[Zardoman]

Thanks Alex,


I am guilty of not reading the manual page to page, and it's not like the manual has a section indicating "noises/devices go on after shut off". Either way, thanks for going the extra mile sending me the link, much appreciated.

[Zardoman]

so is there a section on the second part of my question, anyone experiencing occasional long turn over on the engine? or is this in the manual too?


Alex you've read the manual page to page, so I know you're the man to ask!


Thanks again!

[mav1178]

Originally Posted by Zardoman

so is there a section on the second part of my question, anyone experiencing occasional long turn over on the engine? or is this in the manual too?


Alex you've read the manual page to page, so I know you're the man to ask!


Thanks again!

If you don't want to read the manual, do what I did:

Go to www.subaru.com and find the various sections of the BRZ manual in PDF.

Open, use CTRL + F to find keywords.

I never read the manual page to page, but when issues or peculiarities came up that was where I started.

-alex

[Zardoman]

I get the long turnover start randomly, maybe 2-3 times since I've bought the car, it happens in both scenarios if I haven't driven the car for a few days or just restarting the car after I stopped for 20 mins.
manual says engine may not turn the first time after battery recharged, but will turn over the second time. It doesn't say when the battery is function normally. (unless my battery is already start to go.)

[mav1178]

Since the car turns over slowly, you may want to check the battery to see if it's holding charge properly.

-alex

[andrew20195]

Originally Posted by Zardoman

I get the long turnover start randomly, maybe 2-3 times since I've bought the car, it happens in both scenarios if I haven't driven the car for a few days or just restarting the car after I stopped for 20 mins.

Is it turning over slowly, or is it turning over at a normal speed and just takes longer than normal to start?

[Zardoman]

it actually turns over "normally", just it takes longer. usually it turns after say, take less than a second to turn, but when it "happens", it takes like 2-3 seconds, as I hear it, I am anticipating it doesn't turn.. but it always does, so far.


And yes my initial assumption was the battery, but it didn't sound like it, that's why I suspect is something else.

[andrew20195]

It's possible you could have the issue with the cam sensor air gap, although mine has exhibited similar behavior on rare occasions. That issue will usually set a code as well.

I know that on the new Forester XT there is about a 1 in 200 chance that the engine will stop in a particular orientation. Due to this particular cam orientation on startup combined with catalyst warmup mode this results in an extended crank. It may be that a similar condition exists on our engines, in which case it would be a normal characteristic.