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Dashboard gurgling

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13K views 25 replies 10 participants last post by  slayme1969  
#1 ·
Hello all,

I have some gurgling going on in my dashboard. It seems to only happen when I'm accelerating and/or coming up off the clutch. Any clues? My heat works just fine.

Thanks :thumbup:
 
#2 ·
Sounds like air in your system that needs to be purged. You could still have heat if there is air. I just flushed my core a month ago and the day after I had blazing heat and gurgling in my dash. Not sure if the pedals are related.
 
#6 ·
There is a weep hole on the heater core hoses (usually the passenger side hose). Usually if you hear the gurgle, it's air up in the heater core. It can be a bit difficult to get the air out of the system, but bringing the coolant tank up higher than the heater core will help. Once the car is up to temp, you should be able to bleed the air out through the weep hole on the heater core hose until you get a steady stream of coolant coming out.
 
#8 ·
This thread should help show where things are:

http://www.passatworld.com/forums/showthread.php?t=255973

The heater core hoses are located under the rain tray, next to the battery. Once the rain tray is off, you should see a piece of corrugated tubing that surrounds the heater core hoses. The tubing comes off and will let you see the connections to the heater core and the weep hole should be either behind or directly under the clamp on the passenger side hose.
 
#14 ·
The hole in the heater core hose needs to be slipped back off the pipe, once back far enough, the air should start to purge from the hole once the system is up to temp. You do not need to totally remove the hose, just slide it back far enough for air / coolant to come out.

it should be a small allen bolt that plugs up that hole on the passengers. Your supposed to pull back that hose a lil bit to access that lil bolt and it allows you to get the air out.
There are (2) bleeder screws on the V6, one towards the front of the car, just below the front of the engine cover and another towards the rear. They can both be used to help get air out of the system, however they are low spots and since the heater core is the highest spot in the system, the air typically ends up stuck there.

About 10 minutes after I start driving my car after being off all night I will hear some type of liquid moving around from within the dash...I would say it sounds similar to a gurgling noise, but it will only happen once and usually when I go to accellerate from a stop as the engine gets close to or is at the 190 mark on the temp dial. I hadn't noticed this when I first got the car but within 3 months or so I noticed it.

I mentioned it to a few people who had said they've heard that happen before in their cars and it was nothing to worry about. I could be wrong but I think it could be the CTS or Thermostat allowing more coolant into the engine once it gets up to temp.

I noticed this sound before and after I had a heater core replacement over a year ago. I haven't attempted to bother with it as it doesn't seem to be causing a problem.
You are likely hearing a small amount of air in the coolant system, it is most commonly heard when accelerating lightly from a stop.
 
#13 ·
About 10 minutes after I start driving my car after being off all night I will hear some type of liquid moving around from within the dash...I would say it sounds similar to a gurgling noise, but it will only happen once and usually when I go to accellerate from a stop as the engine gets close to or is at the 190 mark on the temp dial. I hadn't noticed this when I first got the car but within 3 months or so I noticed it.

I mentioned it to a few people who had said they've heard that happen before in their cars and it was nothing to worry about. I could be wrong but I think it could be the CTS or Thermostat allowing more coolant into the engine once it gets up to temp.

I noticed this sound before and after I had a heater core replacement over a year ago. I haven't attempted to bother with it as it doesn't seem to be causing a problem.
 
#19 ·
Okay, so I let the car warm up and pulled the left hose back slightly, and what looked like hot water came bubbling out. I only did it two or three times for a few seconds each. I got back in the car and the gurgling was still there. How long do I let it "bleed" for? Will it drain out through the bottom?

Thanks again for your help.
 
#20 ·
The rain tray does have drainage holes, so the coolant that spills out should drain through, but you may want to check / flush it with some water as they can get clogged.

Some cars seem to bleed really quickly and others seem to be a real pain to get all the air out. My 2002 V6 was a nightmare for getting air out of the system. If you are fairly certain you have purged all the air, but it is getting air back into the system, you may want to check over the cooling system for leaks or anywhere air may be able to enter into the system.

When I was bleeding mine, I would bleed it out based on the heat coming from the vents. If it keeps hot air at idle, all the air should be about of the system. If you air temp drops when at idle, it's likely there is still air trapped in the system.
 
#21 ·
? about purging.

I flushed out the heater core and got a bunch of stuff out.. no heat to heat! Nice.. but it cools down at idle and if figured I had air in the system. Now my heater core line w/ the bleeder is pretty corroded and started to crack and a piece broke off at the end when trying to put the hose on for the flush. It doesn't leak once I put hose all the way back on w/ clamp.

I tried to lift up the coolant reserve and got some air out and did this for aprox 20-25 min w/ engine running.

After reading through a bunch of threads on the heater core flush I don't see anything saying when trying to bleed system do you keep cap on reserve tank or keep it off? When you try to use bleeder hole to you keep the cap on or off?

If I can't use the bleeder hole what else should I do to bleed? Is the reserve enough to get air to bubble out if it is raised high enough w/ cap off?

Thanks.

Michael
 
#23 ·
I flushed out the heater core and got a bunch of stuff out.. no heat to heat! Nice.. but it cools down at idle and if figured I had air in the system. Now my heater core line w/ the bleeder is pretty corroded and started to crack and a piece broke off at the end when trying to put the hose on for the flush. It doesn't leak once I put hose all the way back on w/ clamp.

I tried to lift up the coolant reserve and got some air out and did this for aprox 20-25 min w/ engine running.

After reading through a bunch of threads on the heater core flush I don't see anything saying when trying to bleed system do you keep cap on reserve tank or keep it off? When you try to use bleeder hole to you keep the cap on or off?

If I can't use the bleeder hole what else should I do to bleed? Is the reserve enough to get air to bubble out if it is raised high enough w/ cap off?

Thanks.

Michael
I bled out mine with the overflow tank cap on, but left it bolted to the anchor points. I did also try bringing the overflow tank up above the heater core, but had better results getting air out of the core with it still bolted down. I have seen a few people that create a "cone" out of a piece of rolled up plastic to put in the top of the overflow tank, essentially making it the high point in the system. I tried that method as well, but had no luck getting the air out of the heater core.

If the heater core connection is already broken / fragile, I would be very cautious about using the bleeder hole on the hose. If the heater core connection at the firewall breaks, it will require something either gets rigged up to make it work, or replacing the actual heater core.

There are several companies that make a vacuum fill system that are reasonably inexpensive. Fortunately I was able to bleed all the air from mine after 10+ attempts, but if I had to do it again, I would look into the vacuum fill system and save myself the headache.

Ultimately you are trying to get the system to build pressure and push the air to the high point, unfortunately the high point is the heater core so it is very easy for air to get trapped in there. In theory, bringing the overflow tank up higher than the heater core should create the new high point, however my car just would not let the air out of the core regardless of where the overflow tank was positioned.
 
#22 ·
Crazy..

This just started happening to me a couple weeks ago! I suspected it had something to do with the coolant / heating system.. I've got plenty of coolant and no leaks underneath the car (except for a tiny bit of PS fluid.. thats next). But the heat works great both at Idle and at higher RPMs. Will this cause future problems? That's really odd that this is happening to people all of the sudden.
 
#24 ·
Jon- where would one find the vacuum fill? Is it worth going to the dealer or a local euro shop? Or something one can get/do by themselves?

I tried to bleed the system today using the bleeder hole. Seemed to get a bucnh of air out (bubbles like when looking for a leak in a tire) Once it stopped bubbling and was just leaking out I figured the air was out. I drove around and after a few minutes the heat went back to luke warm/ cool at idle. Both hoses are now hot as before only right one was hot. To top things off when I came back home i was tring to pull hose back a little to see if anymore air would bubble out and somehow i basically pulled hose off and sprayed antifreeze all over. Probably got a bunch of air in again.. ughhh... so point being.. would that work after driving to try and bleed the line from the bleeder hole?
 
#25 ·
Thanks a good question... I'm not sure how many shops would have the proper equipment, I would assume most do, but you should be able to call and ask specifically if they have the ability to vacuum fill a coolant system.

The kits I was looking at ran right around $100 and were meant to work with an air compressor. I know that quite a few different companies have them available (SnapOn, etc...), but I did most of my searching on Google.

As with most things, there are going to be cheap kits which are probably fine for the home DIY environment, then elaborate systems for a shop environment. Here is a link to a quick search on them:

http://www.google.com/#q=coolant sy...lDA&sa=X&oi=mode_link&ct=mode&ved=0CBkQ_AU&biw=1457&bih=935&fp=2c86cc053c827e4c

As far as your current situation goes, unfortunately it is likely air did get into the system when the hose popped off (happened to me as well). To bleed the air out, you will want the system pressurized. When the car is under load, the water pump is spinning and coolant should be flowing through the system quite freely. Once you let off the throttle, the pressure in the system will build up. I found there was usually 10 - 20 seconds after the throttle was let off to have the optimal pressure to bleed out the weep hole. It really helped having a second person hold the throttle at 3k RPM for a few seconds, once they let off, I could fight with the hose.

Like I say, I certainly went through a massive amount of frustration with trying to get the air out of mine. If I had to do it again, I'd order a vacuum fill system and be done with it the first time.