How VW Coolant Bottles Fail

My coolant bottle just broke and I knew I could count on the humble mechanic for the right info. Thanks

My 04 Jetta was running hotter than normal. I had already changed the reservoir and cap. I then changed both the thermostat and ects ( engine coolant temperature sensor). Well everything is perfect again. I don't know which part was the problem, but since I had to drain the system I thought I just change both parts . Thermostat was$9 ,sensor was$17

Thanks My friend. My 2013 Tiguan had this happen today omw home today. Watched the temp like a hawk when I pulled over. Temp read like it always does. Letting the motor get cold. Now I know what to look for. Thank you much!

Thank you very much HumbleMechanic. Very clear explanation, very informative.

hello . do you know the adaptor to screw on needed to pressure test thesecooling systems?

very helpful video, answers a bunch of questions I had. Thanks so much for posting.

Hi. I watch all of your videos. I don't know if you answer questions, but I have a question about my 2004 2.0litre Jetta. It just started to run a little hotter than normal. The temperature always ran with the gauge straight up in the middle. Now its more like 1 o'clock. I changed the reservoir and cap because there was small leakage around the return line. I also bought a thermostat and a coolant temperature sensor. What does the sensor do? Does it control hi and low fan speed?. I'm not sure how the cooling system works. Thanks

You keep saving me money!! Very straight forward. Thanks!

best video yet on this subject. I have 2001 Jetta. Have flushed and filled with VW coolant. Always the one sensor rod closest to firewall corrodes. have replaced 2 times. No coolant migration. Even after flush/fill, coolant gets brownish. Could this be oil and could it be due to a bad oil cooler or seal? Thanks

Hello I have Polo 1.2 12v 2001 when car is cold the water level is on Min and when it reach the working temp it comes to Max . what could be the issue, maybe air pockets, does this system circulate water by it self and remove air from system i dont know . All suggestions and advice's are welcome . Thanks

Will the coolant bottle In the Mk4's make the low coolant light go off? I checked for leaks their is none. I've used Pentofrost SF coolant. My Jwagon has been going through a lot of coolant lately..

Do you know what pressure the cap will start to vent at with these bottles? Looks the same as a '15 Audi A1 bottle.

Just thought I'd mention this, as I had an issue with coolant level sensor on a Skoda (same as VW & Audi). The 2 prongs in the bottle dont relay resistance the cluster module calculates capacitance. This type of sensor is called a capacitive sensor.Similar arrangement also used in the sump pan to detect oil level, but the capacitance calculator is built into the oil sensor.

Hey y'all, I just replaced a few cooling system hoses on my diesel 1986 Westfalia Vanagon but wasn't sure which wires go to which poles on the expansion tank sender. Any tips?

all old mk3's have the bottle so fuzzy you can't really tell how much coolant is in there.

Hey man, so as I'm coming home from a road trip today I got the coolant light go off, maybe 10 mins before I got home. A hose broke off from the nipple it was connected on. It's a hose that is on the right front side of the engine bay on my mk6 gti 2.0 tsi. Right next to the air cleaner box...was wondering if you might know the name of not the hose, but what it was connected to?

hi mate I have an audi b5 1.9tdi on 2001 plate just wondering why there is third connection for a coolant pipe underneath the filler cap is this a vent of some kind or am I missing a pipe somewhere for reference my engine code is alm thanks dude

Thanks for the video! Saved me some dough and a trip to the dealer for something in my wheelhouse!

my vw 2000 beetle I replaced thromast and fill coolant in bled air out couple days later when I drive like 30 to 45 mins I got red temp light blinking and shut down the engine and let engine cold a little bit start engine drive 30 to 45 mins the light comes on sometimes on sometimes good coolant level is good no leaking found what is the cause the red light on? coolant bottle?

MK4 I have boils and the coolant antifreeze presure and wanna come out. What do you think it's the problem?