Your diagnosis sounds possible. Try and get someone to have a look. I find trying to diagnose an engine problem without actually being there quite difficult.
The car rolling forward isn't that surprising to me. It depends on the compression ratio to stop so something with a low comp ratio e.g. something with a turbo would be easier to turn over, a diesel would typically be harder. When the car moved while in gear it was the same thing as bump starting.
I was taught to park in gear to stop thieves - they lift the back wheels to evade the handbrake but the gear locks the front (on a fwd car).
On a hill I was taught to turn the wheel so that the car, if it moved, would roll against the kerb.
Your diagnosis sounds possible. Try and get someone to have a look. I find trying to diagnose an engine problem without actually being there quite difficult.
The car rolling forward isn't that surprising to me. It depends on the compression ratio to stop so something with a low comp ratio e.g. something with a turbo would be easier to turn over, a diesel would typically be harder. When the car moved while in gear it was the same thing as bump starting.
I was taught to park in gear to stop thieves - they lift the back wheels to evade the handbrake but the gear locks the front (on a fwd car).
On a hill I was taught to turn the wheel so that the car, if it moved, would roll against the kerb.