My audi coupe is over heating, Need Help

[naz121]

Hi ive changed the radiator with a brandnew one also new water pump, new thermostat flush the system but my car over heats when idling and driving around, even the fan comes on, my car splutters and bubbles from the resavoir tank boiling water shoots out, i thought it might be a air lock ran the car for 45 minutes and still bubbling , the rad pipe on top is bubbling when i feel it , return pipe is not flowing properly and steam is coming out continously. any help or advice would be grateful ive checked for mayo in oil and water for oil both is clear.

Help!!!

[Crasher]

Year and engine type would help!

[naz121]

Its a 1994 2.0 16v ACE engine

[Crasher]

You need to get a combustion gas check done on the cooling system.

[scotty33]

You could check that the O rings on the expansion cap are in good condition and in their correct position (in the grooves). Experience talking here! Also see if you can see anything wrong with the relief valve built into the cap (spring and ball bearing arrangement). Either of these could cause it to boil over.

[naz121]

Problem is sorted , i had a nasty airlock in the system took me 2 hours to solve it, it seems the only way to bleed the system is from the outlet pipe on the heater matrix, i took the pipe off with the car running and until all the bubbling stopped and nows its fixed.