1999 Vw golf heater problem

[Spudjg]

why has my golf heaters suddenly stopped working? I am getting an over heating problem to suddenly yet my oil and water levels are spot on??

[Tim Baxter]

Usually the heater not working is caused by an airlock in the feed/return pipes or low water level. If you're not losing water I'm at a loss to explain further, although combined with overheating it does suggest water loss.

[Bramble43]

Try this, when engine is hot/warm. touch the heater pipes going to and from the heater matrix, these should be going through the bulkhead (behind the engine) into the car. If one is hot and the other cold then your matrix could be blocked.

You could also have an air blockage, when the engine is cold, remove the expansion tank cap and run the car, keeping the water level topped up, you may lose a bit just before the radiator fan cuts in but can be topped up again straight away, let this happen a few times and refit cap and test heater.