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RSEscort
26-10-2011, 11:51 PM
Hi All,
I have a late 2005 A4 1.9TDI 115BHP, started blowing cold air, building excess pressure in the cooling system and using coolant, after several several checks and consultations with some others failing head gasket was diagnosed, :Blush2:I took the head off, got it pressure checked it for cracks, and had it skimmed, new gasket and bolts used (genuine Audi) rebuilt head and fitted it - car running fine, no pressure & still no heat for about 1000Km then loads of white smoke and using coolant quickly!!!:zx11: tracked it down to the exhast gas cooler on the inlet manifold :Blush2: looks like there was nothing wrong with the gasket in the first place in my book, fitted a new cooler unit (gen Audi) Engine running fine BUT still no heat :zx11::zx11: feed pipe to heater matrix piping hot but outlet pipe cold, with engine running and up to temp i have no flow in the outlet pipe, if i drive the car, leave it running and move out the pipe (top one - outlet from heater matrix)to allow air bleed out through the little bleed hole in the hose i appear to get all the air out, but no matter how many times i do it within 10 min heater is cool again and there is no flow in the pipe if i remove the hose !!!
at this stage its driving me mad --- anyone any thoughts ????:confused::confused::confused:
I should add that i fitted a new thermostat fitted before head removed, engine heats up quickly and stays at 90 all the time, never got hot nor dropped back from full operating temp once it reaches it any assistance would be greatly appreciated:approve:

GarJE
27-10-2011, 08:09 AM
Heat up the end of a piece of pipe and ram the soft part over the expansion tank opening. Loosen the top coolant hose going through the bulkhead near the battery (highest point on the circuit). Blow hard on the pipe and undo the hose so a small jet of coolant can escape. Keep this up until a steady stream of coolant comes out, then re-attatch coolant hose. Most reliable techn.ique i've ever used

RSEscort
27-10-2011, 11:19 PM
Thanks,:approve:
Ill have a try of that, although I think I effectively did the same thing by driving it and then pulling the pipe with the engine running thereby using the pressure in the system to push out the air-- I'll let you know how I get on - I'm away until Monday next so won't get to try it until then :approve:

CheerRS

Crasher
28-10-2011, 09:25 AM
Did you fit a new water pump?

RSEscort
28-10-2011, 10:26 PM
yes -- new Belt, tensioner, waterpump, and idler fitted when head off!! -- all audi parts

Crasher
28-10-2011, 11:06 PM
I have has a few 8E heater matrix's get blocked but at least you can (just) change them without taking the car to pieces.

RSEscort
29-10-2011, 10:21 PM
hhmmm!!! Think I'm going to have a go at back flushing the system before i attempt to remove the matrix -:1zhelp:- will update progress in due course :approve: