[mmedlycott]

I recentlty had my passat 2006 2.0L d serviced and oil was found in the expansion tank, following tests it was confirm this was NOT the head gasket and was the result of a faulty oil cooler, this was replaced, along with the expansion tank and sensor.

Ever since then the temp gauge flucuates. It heats upto 90'c but when on driving on the motor way (or above 50) this begins to reduce, all the way down to 50'c.

I have also noted that the water level keeps reducing with no visable sign of where its going.

I have taken it back to the garage a number of times but they say there is no problem.

Can anyone help diagnose the problem.... its driving me mad.

Many thanks,
M

 

[jdiaz]

I can't believe there isn't a head gasket issue, although I once had an Alfa 156 which had similarly "active" temperature gauge.

 

[[email protected][dartmouth]]

When cruising, my coolant temp also dips at highway speeds. I believe it's because the thermostat is stuck open. It only reaches normal operating temps in local, city driving. I plan to replace it during my timing belt replacement.

 

[mmedlycott]

Back from the garage and they have finally found the problem.

Heater Matrix pipes are worped .... probably from the hot oil in the system (original problem)..... this where the water is leaking

and
Therostat (wax filled) is faulty also due to the oil .... flux in temp gauge.

Gasket is ok (thank god).