Where would i find the heater by pass valve. The reason i'm asking its just been in to have new rocker gaskets fitted and theres a plug at the back of the engine thats not connected to anything Would the bypass valve have been disturbed whike they were doing the gaskets ?
Interesting, now this was on a pre facelift model, not sure if yours will be the same, but many years ago had a Mig in Vx garage to do some work, crank sensor and cam belt iirc and noticed when I got the car back no heat in footwells, only to screen

I went back to the garage and explained the problem, asking if anything they had done which could have caused this, understandably they said no

When I got home I had a good look, now I had previously noticed that the controls worked by vacuum, good scout around and found a vacuum pipe out of place, on the manifold and melted, repaired the pipe and refitted properly and all was well.....
