if the pump is running well it's probably either the piping from the pump to the combi valves, the combi valves or the vacuum that actuates the combi valves. Since you are getting faults on both sides I'd guess the combi valves are OK and either the plastic tubing from the pump is broken or you don't have enough vacuum to activate the combi valves.
You can check the combi valves with a vacuum pump or measure the vacuum with a gauge but the first thing to do is just physically check the condition of the plastic pipes from the pump and as mentioned above, the vacuum lines. Also check any relevant vacuum check valves that might be in that circuit too (if any, I don't have V6).
You can check the combi valves with a vacuum pump or measure the vacuum with a gauge but the first thing to do is just physically check the condition of the plastic pipes from the pump and as mentioned above, the vacuum lines. Also check any relevant vacuum check valves that might be in that circuit too (if any, I don't have V6).
