Engine shudders/almost stalls braking

[shepv8]

Gday all,
My 06 LS 2.0L manual focus's engine has started shuddering and almost stalling when coming to a stop using moderate to heavy braking ( its not the brakes).
Its starts and runs fine and even when it starts to shudder it never actually stalls. Once you come to a stop the engine settles to a normal idle.
Interestingly I changed the starter motor last week and I have read that people have had faults with PCV hoses and that these hoses run near the starter motor? I have had a look but cant see any issues.
Any ideas?