change the thermostat, unless you have an air lock, get the engine hot and then check the two hoses on the bulkhead to see if they are both hot. If one is hot and the other cold/warm the heater matrix is blocked.
rivit
November 2005
I can answer this question...
HOW CAN I FIX MY HEATER ON A 96P REG VECTRA ESTATE 2.0L 16V?
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