Losing water need help

Hello everyone first off let me start with if you are reading this thank you for your time. Ok well it starts with my water fill tank I can fill it and drive but after a while it runs low and my red temperature light comes on the car doesn't over heat but I fill it back up was wondering if anyone else has had this problem before is it my water pump first vw Jetta it's a 2.0 gas wagon if anyone can help it would be very appreciative thank you all again
Frankiebusch is online now Report Post Edit/Delete Message Reply With Quote Multi-Quote This Message Quick reply to this message
Reply

Could be a leaky pump or other sources. Time to pop that hood have a look-see


Sent from my iPhone using Tapatalk

External leaks should leave pink crusties if you're using standard coolant.

Check for obvious leaks first. I had a sneaky leak recently. The coolant return hose nipple at the top of the expansion tank was cracked right where it meets the tank. You couldn't see it, and it wasn't obviously leaking liquid. But, I was losing coolant regularly from escape of water vapor through the crack. Finally found it, and replaced the expansion tank.



Brett

Thank you all for the advice I will look it over tomorrow I appreciate guy you guys are awesome

A rather common (and sneaky) leak point is the shaft seal on the water pump. Look CLOSELY around the bottom of the pan right behind the harmonic balancer. It's not uncommon for there to be a bit of oil collecting there but if you see evidence of coolant the odds are high that's where it's happening, and that means it's timing belt time whether you like it or not. If that bearing fails entirely (and it will if the seal is gone, eventually) you're screwed. It is difficult but not impossible to get an inspection mirror in by the water pump pulley from the top with the top timing belt inspection cover off, and that plus good lighting will usually give good evidence of the leak if that's where it's coming from.

There are other common problem points too -- the heater connections at the firewall (easily fixed; O-rings) and, what may be the nightmare one, the X-ring (O-ring but square section) on the hard pipe behind the IP and above the thermostat. That one is a pain in the neck to get to; the actual part is cheap but the time and trouble to get that hard pipe out is a five-alarm pain in the butt. Also check the thermostat housing; that O-ring fails as well occasionally. Fuel leaks from the area of the IP will eat those O-rings over time and is frequently the root cause.

Good points, Genesis. As well as causing o-rings to fail, a fuel leak will soften and cause to fail any rubber hose in the general vicinity, particularly that coolant hose the comes off the hard pipe right there by the thermostat and connects to the bottom of the coolant reservoir. I just had to fix both of those, and what a PIA they both are!

Another fun place to have a coolant leak you can't see is the heater core. My Y2k is oozing - the coolant loss is now quite slow since I fixed the 'easy' ones, but the heater smells like maple-y coolant glycol and my windscreen *just*won't*un-fog* on the inside. Ugh.

Cheers,

PH

A heater core leak is a severe problem you need to fix. Glycol is a NASTY poison and you do NOT want to breathe the vapor; while the vapor pressure of it in free air (even when it gets hot) isn't very high it is one of those things you simply do not want in your body in any quantity.

The bad news is that you have to remove the entire dash to get to it; it's an all-day job and a five-alarm pain in the neck.

I'm having the same issue on my daughters 01 Beetle. Even after I top off the fluid, the red overheat light comes on intermittently for minutes at a time even when the engine is cold. I am 99% sure I have narrowed it down to a faulty temp sensor which is also slowly leaking fluid around the o-ring. It's on order along with a new recovery tank which has sensors embedded and I figure I'd replace as well since I am in the system.

I might interweb guess the level sensor is dirty or inoperative and the red light is telling you it's low on coolant, not over temperature. If it is in fact the temperature sensor, I don't think there is one in the coolant tank. VCDS (or equal) can help narrow this down.