No Heat, Coolant tank pressurised, over flowing, HELP!

Good Morning

I have a 2004 8P Pd140 BKD. 145k

When im driving along i will get a low coolant warning, ill pull over and my tank will appear empty, when i release the cap 'whooosh' the coolant will rush to the max level. This will happen every 20 minutes while driving the car normally. As the reservoir pressurises it pushes the coolant through the over flow (im guessing) whilst driving, I do have to up a litre coolant every other day. I will get the low coolant warning seconds after the temp gauge hits 90. When the heating is on it is barely luke warm, if that.

Work I've done:

• New cap and Reservoir
• Coolant Flush and New Coolant 5050 G12
• New thermostat Genuine part
• New coolant temp sensor Genuine Part

There is no oil in the water, no water in the oil, no mayo, no steam out the exhaust, no leaks, no coolant bubbling, no leaks, no power loss, manifold is coolant free, oil change was clear of any irregularities.

I will be doing a heater matrix flush next to see a possible blockage is the reason for the pressure build up and lack of heat in the cabin.

is it an air lock? blockage? my local indy doesn't have a clue either charged me £50 to put a £4 leak detector dye in the coolant, no luck.

If any one could help me out that'll be great.

Thanks in advance

Thank you for your input guys.

@S3dave1990 @mjr901 @Soot1 The water pump is working just fine. I have bled the system of air and the problem still occurs however there has been a development:

The weather has gone cold here in sunny Manchester lol, and whilst driving today there was plenty of steam (more visible due to the drop in temp) that smelt like coolant coming from the exhaust whilst driving. After some research, my findings point me towards a bad EGR cooler which can apparently leak internally and burn off in the exhaust hence the steam. So as well as flushing the heater matrix this week I will be performing a EGR cooler delete as my EGR valve is blanked off already.

I don't think the cylinder head or the gasket is at fault here, but we will shortly find out through my process of elimination, working my way down starting with the cheapest option first.

Thank you again for your input guys, I will be updating my situation later on this week.

UPDATE TIME

I was unable to do an EGR Cooler delete as the parts didn't arrive on time. But i did find traces of oil in the turbo intake pipe, hence the smoke, is this normal? my oil levels are normal and contaminant free.

However i did flush the heater matrix, drained the system, and refilled with fresh coolant, bled as much air until there was no more air to be squeezed out. There was a lot more heat in the cabin but it still isn't 100%.

I let it idle with the cap off for 10 minutes, no luck.

10 minutes into driving 'low coolant' warning. FML.

@mjr901 Vacuum Sounds expensive? Unless you can do it for me? ;-)

@Soot1 i will order a infrared thermometer, any other way to test a blocked radiator?

Or does anyone where I can get this sorted ?

So EGR valve and cooler delete done and the problem is stil f*ckin there!!!

running out of options here :-( ordered a block tester kit to check for exhaust gases, should be here this week

However I have now got this fault code could it be related??



Address 08: Auto HVAC Labels: 8P0-820-043.lbl
Part No SW: 8P0 820 043 D HW: 8P0 820 043 D
Component: KlimavollautomatH12 0150
Revision: 010059 Serial number: 8P0820043D
Shop #: WSC 00000 000 00000
VCID: 2D51EF3FB4E4E5760F5-8078

1 Fault Found:
01274 - Air Flow Flap Positioning Motor (V71)
003 - Mechanical Failure - Intermittent
Freeze Frame:
Fault Status: 00100011
Fault Priority: 3
Fault Frequency: 180
Reset counter: 38
Mileage: 227538 km
Time Indication: 0
Date: 2015.09.18
Time: 06:59:53

Freeze Frame:
Voltage: 13.60 V
Temperature: 11.0°C
(no units): 170.0
(no units): 34.0
Temperature: 10.5°C


Thank you