[ff1609]

I have a May 2010 Dzire Ldi which has done almost 40,000kms. For about 6 months, I've been hearing a weird noise of fast flowing liquid from the engine bay. The noise goes up on acceleration and it is there about 60% of the time when I drive. Its not a faint noise, it is fairly loud, even the back seat passengers can hear it. When sitting inside it seems as if the sound is coming from behind the dashboard.

It is not the AC because whether I use the AC or not, the sound remains. I read somewhere online that this could be cause by air trapped in the narrow ducts/tubes that carry coolant.

Coolant level always remained constant, last month the A.S.S suggested flushing the coolant and that took care of the noise for about 3 days. I did not check the coolant level until a week after service, until I noticed the temperature gauge at 3/4th of full heating. Stopped the car and let it cool down, noticed that there was almost no coolant, it took 3 liters of water to fill the coolant reservoir as a temporary fix. However, a thick gray precipitate appeared on top of the coolant reservoir. I suspected the head gasket is gone. (Though the engine oil dispstick or the filler cap didn't show any sign of moisture in it).

Took it to the A.S.S and they immediately said the head gasket is gone, I left the car there and then they said it is not the gasket, perhaps someone forgot to fill in coolant (really convenient). Anyway they filled in coolant again.

In 3 weeks, the coolant level went down by about a liter (I noticed occasionally dripping coolant) and the noise remained, the A.S.S did a flush again, put in some salt like thing to clean the system but - the sound returned and so did the precipitate.

Back to A.S.S, they have replaced the coolant valve in warranty but the noise is back within 2 days, I am yet to figure out if the coolant level is down.

This time after repair I find the car very sluggish, may be it is the gasket. Is it possible that it is hard to notice water/ coolant mixed with synthetic oil?

[buz]

I too get this gushing sound of air at high pressure passing through a tube when I accelerate in my Skoda Laura 1.8 TSI. Have been passing this off as 'adrenalin rush' of the car while revving it but it does concern me as something that I did not experience in the previous car I owned.

[arjab]

Originally Posted by ff1609

I have a May 2010 Dzire Ldi which has done almost 40,000kms. For about 6 months, I've been hearing a weird noise of fast flowing liquid from the engine bay. When sitting inside it seems as if the sound is coming from behind the dashboard.

Cannot 100% accurately diagnose the problem without seeing your vehicle and greasing the palms

However i faced an uncannily similar issue with my 2006 SWIFT petrol which has covered 55k kilometres.
This "sloshing-water-sound-behind-dashboard" happened two months ago - for the first time.
Remedy: The leaf screen was taken out (this is the netted/serrated plastic cover on which the wipers sit).
The rain water channel of the BIW run below this.
In my SWIFT's case the water channels had got blocked due to dried leaves, muck, dirt having fallen into it with the result that water was accumulating inside. Thoroughly cleaned. No recurrence since.

[t18]

Recently changed my alto's radiator fan because of which the coolant was drained. After filling new coolant this water gushing sound started coming whenever I started the car. I checked for coolant level and it was little low, so added some water and the sound has gone. Its been two weeks and no problem. I guess the mechanic did not mix the coolant and water in equal parts.

[condor]

@ff1609, it would not be flow of liquid. It's more likely a problem with cabin insulation (for noise).

Originally Posted by arjab

Cannot 100% accurately diagnose the problem without seeing your vehicle and greasing the palms

@Arjab, I can understand when you say you cant diagnose withouth seeing the vehicle. But why would you want a bribe to diagnose the problem ?

Note:
"greasing the palms" = bribing someone.

[GTO]

Originally Posted by ff1609

Stopped the car and let it cool down, noticed that there was almost no coolant, it took 3 liters of water to fill the coolant reservoir as a temporary fix.

In 3 weeks, the coolant level went down by about a liter (I noticed occasionally dripping coolant) and the noise remained, the A.S.S did a flush again, put in some salt like thing to clean the system but - the sound returned and so did the precipitate.

Your cooling system has air in it. Ask the authorised service station to bleed it, refill with coolant and you are all set. Ask them to lift the front of your car up, put on the heater (HVAC) and revv from time to time. Do this for 15 - 30 minutes.

[ff1609]

Originally Posted by GTO

Your cooling system has air in it. Ask the authorised service station to bleed it, refill with coolant and you are all set. Ask them to lift the front of your car up, put on the heater (HVAC) and revv from time to time. Do this for 15 - 30 minutes.

Thanks GTO, I asked the workshop to do it and they did, because the noise disappeared for about 3 days. I think there is a very small leak somewhere which is causing the air to get trapped again. This is also evident from the slowly reducing coolant level (about 300ml in a week). I think they just need to find where this intermittent leak is, most likely where the hoses fit.

[sgiitk]

@ff1609; You normally see a stain of the coolant where the leak is. Look for it.

[arjab]

Originally Posted by condor

@Arjab, I can understand when you say you cant diagnose withouth seeing the vehicle. But why would you want a bribe to diagnose the problem ?

Note:
"greasing the palms" = bribing someone.

Good one ! by greasing i meant "grease" ! love your wit !

[Catalyst_delhi]

I had those sounds , it is caused by air pockets and localized boiling. It could be caused by bad thermostat , bad hose( cracks) or blocked water passage. Would advise a reverse flush . also checking if there are air bubbles in the degas bottle. (this is the bad if you have - HG repair)

[ff1609]

Originally Posted by GTO

Your cooling system has air in it. Ask the authorised service station to bleed it, refill with coolant and you are all set. Ask them to lift the front of your car up, put on the heater (HVAC) and revv from time to time. Do this for 15 - 30 minutes.

Originally Posted by Catalyst_delhi

I had those sounds , it is caused by air pockets and localized boiling. It could be caused by bad thermostat , bad hose( cracks) or blocked water passage. Would advise a reverse flush . also checking if there are air bubbles in the degas bottle. (this is the bad if you have - HG repair)

The car has been to 2 different A.S.Ss 6 times for the same issue & the sound it still there. Coolant level still continues to go down. I think both the problems come down to a minor leak somewhere which they are not being able to find; as a result coolant leaks and air gets trapped from there.

However, I am also seeing something I have never seen in another car, every time the coolant level goes low, there is a thick creamy precipitate which looks quite like chocolate icecream in the coolant reservoir. If I rub it between the fingers it is not greasy and dries into a powder. Since it is not greasy and there is no trace of water in engine oil, it doesn't seem to be a head gasket issue. Could this be burnt/ boiled coolant?

To give you some history, at around 16k (1 year ago) the pistons and head gasket were replaced due to heating (coolant leaked and the engine seized).

[johnruben]

@ff1609, pistons and head gasket replaced at 16k km? what happened?
looks like someone sold you a lemon.

[Jaggu]

Oil and coolant are getting mixed in the engine, most probably the head gasket job was bad, check the engine oil also to confirm this. Get it attended at the earliest.

[Catalyst_delhi]

Check if the cap is sealing , then check if the fan is working on low and high speeds or if the aux fan works( not sure in your case). But if you are getting chocolate then HG for sure , might be minor now if left then it will lead to pistons scruffing and a whole lot of repairs.

What you are describing is a leak of the oil passage to coolant passage , if the coolant is not blowing out of the reservoir then the fire rings are ok on the Headgasket. check if the head bolts are torqued to spec before dismantling.

summary:
1. check cap
2. check fans( most heating HG issues due to this)
3. check if head bolts are to spec
4. check thermostat ( most probably it would have gone bad due to engine oil.

OT - source: fixing cars with HG issues for the past 5 years (for friends , family and sadly once for me)

[krish82]

Hi,

I am noticing a peculier problem from past few days, i dont remember if this was there before, The problem is when ever i accelarate or brake in my Optra 1.6 i hear sound of water or petrol gushing, like under the right door, dont know if this was normal, i took full tank petrol last time, but the sound is still there.

No petrol smell but, also even when i hit a bumper or pothole i get this sound like water hitting the shore, i checked my car of water bottles, but none is there in the car.

There is no problem with the car otherwise, i can hear the sound only with windows up and AC off / 1 position.

1. Are there chances of rain water accumulating underbody?
2. Or is it normal petrol flowing sound.

Optra owners please help, otherwise i have to take the car to sundaram motors which is bit far from my house.