I've been having a bit of a saga with said cooling system having already had the thermostat, sensors, viscous fan clutch and electric pusher fan replaced. The system has also been pressure tested ok. The official line from the garage (amc london) is that the engine shows no sign of overheating and there was an oil leak from the vanos solenoid (left bank, facing the car) onto the wiring loom likely to be causing a water temp gauge error. Now i have had a second opinon on this which i am inclined to agree with: The oil found on the wiring loom was fresh motor oil on the air flow meter connector. granted, this is close to the vanos solenoid but considering it had fresh motor oil on it it is more likely to be a filling spillage as the oil filler cap is also very close to this area and the vanos solenoid shows no sign of any leaks.
Back to my symptoms:
-If i am driving with no heating on, it will overheat after about 15-20 mins and if i then turn the heat on max the temp gauge goes back to the middle within minutes.
-If i'm on a really long drive with the heat already on, after a while (about 45mins) the tempgauge goes up to 3/4 and hovers about going back to the middle every now and then, the reason i know it is not a gauge error is that every time the gauge goes up my feet or face get roasted...
Now there's not much left to replace on this cooling system but i don't just want to jump in there willy nilly as we're talking about some seriously priced kit. My personal train of thought is that it must be the radiator as the water pump is not leaking and i guess it is circulating as the system pressure tested ok.
Now, does anybody know any specific tests that could be performed to determine if the radiator is cooling the water by the right amount and isn't blocked?
Another thing is, i can only get hot air in the footwell and on the windscreen but not in the vents facing me, and lastly when using the vent on function with the ignition off there is no hot air at all, but i think this is more linked to the final stage resistor and shouldn't really affect the running of the engine?
Any other useful information or advice would be appreciated!