sloshing water noise after servicing!

kris250 · March 10, 2017

Just got the car back and didn't notice until I was home and playing about with the engine. Keep hearing this noise of water slushing about whenever I rev the car or when its starting up. I strongly suspect its the coolant but why can I hear it now? The car has just been serviced and also had the waterpump replaced as the previous one was leaking. They topped it up with coolant too so low coolant doesnt seem like it would be the cause.

Any ideas of what may be causing it and any quick remedies? Definitely do not fancy driving all the way back to Lexus Edgware..

Texas · March 10, 2017

Water pump changed you say? Then I would put money on the 'sloshing' noise you can hear is air pockets moving around in the coolant system, this is not normally a problem unless somehow any coolant temperature sensors end up being in an 'air pocket' in which case the sensors will not detect the true temperature of the coolant and may cause some other errors to be flagged up.

"They topped it up with coolant too so low coolant doesnt seem like it would be the cause."

Have you checked the coolant level now?

One thing I do suggest is that you keep a careful eye on the coolant level in the near future as any air pockets when flushed around to the expansion tank will be replaced by coolant and therefore the level will drop. You are not loosing coolant it is just totally filling the coolant system.

paul m.

kris250 · March 10, 2017

9 minutes ago, Texas said:

Water pump changed you say? Then I would put money on the 'sloshing' noise you can hear is air pockets moving around in the coolant system, this is not normally a problem unless somehow any coolant temperature sensors end up being in an 'air pocket' in which case the sensors will not detect the true temperature of the coolant and may cause some other errors to be flagged up.

"They topped it up with coolant too so low coolant doesnt seem like it would be the cause."

Have you checked the coolant level now?

One thing I do suggest is that you keep a careful eye on the coolant level in the near future as any air pockets when flushed around to the expansion tank will be replaced by coolant and therefore the level will drop. You are not loosing coolant it is just totally filling the coolant system.

paul m.

Well, anyway to get rid of this problem then? Or is this something that they would need to sort out?

Texas · March 10, 2017

I am not yet au fait with the IS250 to the level of others on this forum who may have more learned advice but the water pump should push the coolant around the system at a rate to hopefully dislodge any air pockets and eventually the problem should subside. Use of the cabin heater may assist in this as the coolant will have more flow, just keep an eye on the coolant level like I said as it will drop as the air moves higher, I am thinking that after the pump was changed the coolant was not refilled in the prescribed manner ( with a temporary header tank while engine is running) and was just refilled probably without engine running.

paul m.

NemesisUK · March 10, 2017

Try running the engine with the header tank cap removed, see if any air bubbles escape?

johnatg · March 11, 2017

You certainly have air in the coolant system. The heater will make no difference - heater matrices these days are always hot - the temperature is controlled by flaps and air mixing. The system must not have been bled correctly during filling. Thing is - you need more pink coolant to top it up. Do you have a Toyota dealer nearby? - might be worth seeing if they will sort it for you to avoid a long journey

Texas · March 11, 2017

Just a note on this 'problem'. In the past when I have had this 'gurgling' noise in the coolant system after changing the thermostat for instance to expedite any air removal I have used a local (non fee!) high rise car park and after running up and down in there a couple of times it dislodges the air pockets!

Paul m.

kris250 · March 11, 2017

Tried everything you guys suggested - nothing work. Left it running for around 20 minutes or so with the cap off and could see loads of air bubbles escaping but still carried on making the noise after around 25 minutes or so. Its going back to Lexus on Monday. Will not be going to Edgware again as this isn't the first thing they cocked up for me

is200 Newbie · March 11, 2017

Is there coolant in the expansion tank?

kris250 · March 11, 2017

26 minutes ago, is200 Newbie said:

Is there coolant in the expansion tank?

The reservoir behind/under the intake?

is200 Newbie · March 11, 2017

The expansion tank is behind the front grill - black cap if I am not mistaken

kris250 · March 11, 2017

Okay so I took some photos, fairly dark but the tank looks empty to me.. I cant really compare with anything else since I've never looked at it when full - can anyone check the photos and confirm?

Also should mention that when the coolant cap is off I see nothing there - it only starts bubbling up when the engine starts running.

johnatg · March 12, 2017

It looks pretty empty to me. It should be 2/3 or so full with pink coolant. (There are max and min marks). Indicates that, as I said, the system was not properly bled during filling. Not sure that it's too great an idea to drive it a long distance like that. Is there no Toyota dealer closer? They might do you a favour and sort out Lexus Edgeware's incompetence!

is200 Newbie · March 12, 2017

I am pretty sure the level is indicated on the tank with COLD stamped on the tank. As a guide, use the jointed seam, seen in the second picture on the tank, as a guide level. If you overfill then it wont cause damage as it will expand out of the overflow pipe when running (make sure the overflow pipe is not blocked)

I would not drive it as a precaution as you don't know how much coolant is in the system, you may cause damage.

If no dealers near you then you can purchase the correct fluid and get it despatched to you. Try Lexus Birmingham on ebay or eBay itself - I would recommend you get at least 2 litres (topups come in 1ltr bottles) if any spare when topped up then you can use this if required while monitoring the levels.

Vintagesixtysix · March 12, 2017

I put a small torch up against the expansion tank wall.....just helps me spot the levels.

Sent from my iPad using Lexus OC

kris250 · March 12, 2017

The nearest is about 1 hour away from me. I already drove the car 2 hours on Friday when I picked it up from Edgware which I hope hasn't caused any damage.