Just been out giving the Astra some, lots of high revs etc etc and now and again I'm getting a loud pop from the engine bay not exhaust Although the car seems to run fine, infact its running better/faster than it ever has!
It only happens now and again and mainly when decelerating or blipping the throttle. Any ideas to what this could be? I was thinking inlet manifold leaking causing the engine to run lean, it sounds the same as my old throttle bodies when back firing through one of the trumpets when the car wasn't running right. I've got no ECU light or fault codes stored. My AFR hardly ever reads rich even when booting it.