Heater Matrix - Airlock ? -
18th March 2017, 08:35 AM
I've had this before and cured it pretty simply. However, please take care as the coolant will be HOT.
1. Run the car up to temp until the fan starts.
2. Turn the heater up to hot and the fan to medium
3. VERY SLoWLY loosen the coolant cap. You may hear it hissing and then bubble. BE VERY CAREFUL. Remove the cap and gently increase the revs. You may see bubbles coming through.
4. After about 5 mins of the above, turn off and top up coolant.
5. Repeat step 3 and 4 until coolant level remains constant.
The gushing sound should then have gone and heaters working as normal.
You can bleed the system using the bleed screw but it's a PITA to get to.