At low revs I can hear a quiet running water sound on the passenger side of my MY03 2.0 sport wagon. Comes and goes as I gently rev the engine. Anyone know what this could be? I figured it could be coolant working it's way past a partial air lock or something.

 

air con maybe i used to hear mine on a different car i had

 

Thanks. I wondered that but it does it when the AC is off. I read on another thread that it could be air in the heat exchanger in the cabin. Not sure how to get the air out if so.....

 

I get the same and I have a 2006 STI, Only when I gently rev???????

 

I read an an Aussie subaru site that it's air in the heater matrix behind the glove box...

 

top up the air con,mine was doin this last week just as the air con kicked in,paid 25 quid for top up noise gone

 

Not sure if its any thing to do with the A/C because it still does it with it turned off???

 

The Matrix ? I don't want to go into a computer generated world and I am certainly not the one

 

My 04 WRX does exactly the same. I think someone told me it was the water circulating around the heater matrix ?

 

If it is air in the Matrix is this normall ? Or should we be trying to bleed the air from it

 

Yeah guys theres been a post on this
I have the same 'problem'
Its a scooby thing............not anything bad.
Just annoying!

 

Had a look at your scoob, Love the colour was that standard??

 

Ah cheers mate
Yes it is thanks
Red mica 94h
I wanted something a little different
Getting my sti scoop put on this week
What you jumping about in bud?

 

Exactly the same sound on my MY06 STi Hawkeye I thought that it was the fuel pump as mine has PPP????

Simpsons !

 

My MY03 WRX does it i believe its air in the matrix. Dont know if its worth investigating. My classics never did it

 

Having asked the question, I am hoping this is the answer. I googled the topic and found some advice from "edmunds", US site, which I have pasted below.

Sure enough, when I took the cap of my radiator it was not full despite the reservoir being above full. In fact, it took about 1.5 litres of coolant before it filled up. This makes sense as I can imagine that excess air in the system could reduce suction on the reservoir to the point that it fails to top up the rad automatically. I'll find out whether or not the fix works on my drive to work in the morning. Let me know if this works for you - cheers:

First, while your car's engine is cold, check the coolant level at the radiator fill neck, NOT the overflow bottle atop the right front inner fender (which will be partially filled with a green fluid.). At the radiator fill neck, there should be green fluid right up to the sealing ring (located about an inch or so below the top of the neck) in the fill neck. If it's low, air may've become trapped in the heater core. Add a 50/50 mix of antifreeze/demineralized water to bring the level up to the sealing ring. Once that's accomplished, if the level of coolant mix in the overflow bottle is low, bring it up the molded midline. You can buy antifreeze-coolant pre-mix at any autoparts store or the automotive section at discount stores - just look for the designation(s) "Pre-mix" and/or "50/50". Actual brand is unimportant - even if it's a long-life formulation (Since Hyundai uses a standard antifreeze, you won't gain any advantage using a long-life product for top-up. Most antifreeze sold in North America, now, is long life specification. The important thing is that mixing them will neither cause harm nor reduce the working life of the original coolant.). Next, set your automatic heater/air-conditioning system to manual, manually advance the heater control valve ALL the way to the hottest setting, and then drive the car for a few miles - there might still be air in the heater core that requires purging. A good drive or two should purge it out. (You do not have to run the fan during all this but doing so to maintain comfort is perfectly acceptable. The main thing is to keep the temp control to full "Hot" while purging any trapped air out.) If this solves the gurgling-noise problem, you're not done, yet. Keep close tabs on the coolant level over the next several days - again, at the radiator when the engine is cold. Some slight loss followed by a stable level only indicates any remaining air has been purged out of the system. However if the coolant level continues to drop repeatedly without stabilizing, you have a leak somewhere which will require the services of your dealer and would likely be a warranty claim at this stage of your car's life.

(Ethylene glycol-based antifreeze, attractively dyed, and, along with its pleasantly sweet aroma and taste, is equally very tempting to small children and pets. It's also lethally toxic in relatively small doses, so immediately wipe up spills.) //

 

I have not had my Subaru for long but I also heard this noise on start up some mornings, checked inside and out side the car for leaks but could not find any so I thought this was just the noises Subaru's made

I check my oil & water every weekend, my oil is fine and does not need topping up but over the last couple of weekends I have had to top up the coolant by about quarter of a Coca Cola bottle which is about 140ml.

How do I purge/bleed the air out of the system on a classic???

 

most scoobys gurgle mate dont worry about it pal its just the air con it be fine

 

most scoobys gurgle mate dont worry about it pal its just the air con it will be fine

 

My aircon is empty as will be being removed soon & always off so cannot be aircon, its sounds like trickling water!!!

 

It's air in the coolant

 

How do I purge/bleed the air out of the system on a classic???

 

Air in the heater matrix defo

 

Hi mate iv got a 2006 STI SpecD, with Prodrive back box and scooby world mud-flaps and about a grands worth of ICE.
Waiting for the warranty to run out in March so I can get both cats out and replace with one sports cat and a remap by Jolly Green Monster

 

it cant be air-con can it??? thought air con was special gas stuff????

anyway its gonna be a air lock in the matrix, it doesn't matter what car you have you dont expect to hear running water, if you do hear it you know you have an air lock, THIS IS NOT NORMAL.

subaru's are also well known to be hard to bleed sucessfully.............

if you think about it, its common sense

 

You are right mate ac makes a kind of swooshing noise when low on gas.
Not sure if its a air lock maybe a little bit of air trapped in this Matrix thing because I have no problem with the heater or the cooling of the car

 

The solution I posted worked for me. The noise has pretty much gone. I plan to keep an eye on it for a few days and keep topping up the radiator as the remaining air works its way out. Whilst the noise may be common / accepted I think it's probably fixable in the same way in many cases. My lesson learned is: don't trust the coolant reservoir level, make sure the radiator is full and not air locked.

Thanks for all the posts.