Temp red light blinking

[Paradoxx]

Hi all, I've reading all of the thread talking about this red temp light blinking but I didn't found any similar as my problem is. The situation is this, The red light blinks because the level of coolant is low. But I've already checked everything and it doesnt has any leaks. I thought it could be the water pump but that doesn't cause to have a low level of water, neither the temp sensor. Maybe im thinking that I dont have a 100% of coolant because is mixed with water......maybe, please you guys tell me, and if you need more details, please ask them. Regards.

[btb]

Either it's a false alarm or a real deal.
False alarm:
-Bad coolant temp sensor (at the heart valve, driver's side of the engine)
-Bad coolant level sensor (2 prongs inside coolant ball)

Real deal: overheating!
-water pump is going south
-sticky thermostat
-whacky cooling fans or thermoswitch

[Paradoxx]

yeah, I thought about the thermostat and I might change it. But the thing is that coolant level it does go down, wheres is it going that coolant if theres no leaks is it evaporating?

[btb]

If the coolant level goes down, it definitely has a leak somewhere. The "heart valve" is usually a culprit.

[mezonesxbox]

Ok, i just finished paying my 500 repair for this type of problem. Actually i get this every 9 months or so. My mechanic says i drive it too hard.

The thermostat is good if the upper hose gets hot after a while; meaning coolant is flowing in. No coolant leaks really tells me it could be a bad waterpump, last year my pump's imellers shattered in pieces and i keept running unknowing of the problem and almost cracked my engine's head. The whole repair was 1800 because the mechanic had to do a whole re-built pretty much.

Leaks can come from the reservoir itself,coolant flange ( a Y shaped plastinc pipe located by the airbox which cracks over time) Or a leak can also come from the pump itself and drip down your oilpan. Also even if the waterpump impellers are fine i also found out that over time pressure and stress break a seal in the waterpump that also causes a leak. Double check the car before you keep on driving. Also try clering the codes and see what happens(could be a sensor)

[mezonesxbox]

Originally Posted by Paradoxx

yeah, I thought about the thermostat and I might change it. But the thing is that coolant level it does go down, wheres is it going that coolant if theres no leaks is it evaporating?

Quick note, check you oil. If it looks like a milkshake you got broken heads...

[Paradoxx]

BTB, which one is the heart valve?

Mezonesxbox, the funny thing is that I dont have a check engine light. My girlfriend told me that today in the morning she saw the car left a water spot on the floor at the opposite of the coolant reservoir, maybe that Y flange you're telling me about, I have to look for it because I had never seen that one before.

[btb]

The Y flang is actually the heart valve. You can get it here http://www.germanautoparts.com/Volks.../Cooling/117/1
It's #12 in the first diagram and another diagram tells you where to look for leakage. It seems like your heart valve is leaking. Good luck.

[Guilty_as_charged]

I think someone must be after my wallet because my car is now costing me out of my ass. I just got this problem to I am not sure what the issue is however the coolant level looks about right. However I will be driving by VW dealership later today do get some more coolant. I don't know what else I can do and I really don't like having to drive it when it is having issues.

[Paradoxx]

thanx BTB, youre very kind. I'll be chechikng this thing and let you know my results.

[Paradoxx]

I disassemble the heart valve and in deed it was broken, I guess the last owner has a bad mechanic dude because it was too tight, that cracked the part from the inside and let the coolant go thru the o-ring. I got a new heart valve for Q120 = $13. Im installing it tomorrow first thing in the morning. Does anyone knows the right procedure to drain and fill the coolant the right way?

[Genesis]

I replaced the Coolant Heart Valve yesterday. Added the Volkswagen approved Coolant and Bled the air out of the system. The whole procedure was fairly painless and I was happy after everything was all buttoned up. I let the car run for a while and thought everything was good to go. I didn't pay attention to the fact that the heat was working in the car until I left the garage and was headed home. I had driven a block away from the garage when, the engine over temp light started flashing. I returned to the garage and the coolant was boiling over. I check to see if the system had an air pocket and all checked good. I finally realized that the heat was working. So I submissed that the water pump and/or the thermostat were defective. I called the dealership this morning a they wanted $950.00 parts and labor to do the job. This included the pump, thermostat, timing belt and timing belt tensioner. I found the same parts including the thermostat gasket and serpentine belt on GermanAutoparts.com for half the price. I've also decided to do the work myself and avoid the dealer/stealership.

[Genesis]

Originally Posted by Paradoxx

I disassemble the heart valve and in deed it was broken, I guess the last owner has a bad mechanic dude because it was too tight, that cracked the part from the inside and let the coolant go thru the o-ring. I got a new heart valve for Q120 = $13. Im installing it tomorrow first thing in the morning. Does anyone knows the right procedure to drain and fill the coolant the right way?

There are two ports on the top of the Heart Valve Flange. One is the coolant temperature sensor and the other is to bleed the system. Once everthing is replaced and put back together. Add coolant to the coolant reservior. Start the ignition ensuring that you turn the heat on full blast. Add coolant as needed. Once the coolant level in the reservior no longer drops below the max line, pull the retaining clip from the bleed port and pull the plug. You'll hear air leaking from the port and the coolant level will rise and lower in the heart valve. Once the level leaks out constently you're good to go. Plug up the port and reinstall the retaining clip. Be sure to keep an eye on the coolant level in the coolant tank. Top it off to ensure that you are good. If you need to, add water to the mixture after you've emptied the coolant bottle. The mixture is rated at 50/50. The only coolant that you are suppose to use is the G-014 from the Dealer.

The heart valve normally goes out every 50,000 miles. I just hit the big 50,000 and mines looked just like you've discribed hear.

[phatmonk]

So I have all these same issues with my 2003 beetle and my fan isnt comming on either.I replaced my thermostat and my red overheat light is still coming on.I read here I also need to bleed its cooling system?I have rebuilt plenty of old BB engines but I am stumped with all this sensors.The radiator was not low on coolant either,I also noticed that when I started the engine with the thermostat housing off the motor didnt pump any fluid out the thermostat housing/Block with no thermostat in it.Help please.I dont have the cash to take to a dealer but i do have plenty of tools to get the job done.I also have condensation on the oil fill cap but no moister on the dipstick or any oil and water emulsion

[Smileybug]

Have you replaced your water pump? Also maybe try the fan switch if your fans aren't coming on.

[phatmonk]

Where is the fan switch located at?
Thanks in advance