Ok guys looking for some help....car is an astra h vxr, the car just doesn't seem to be running right. Sometimes when accelerating from 2k/3k revs the car doesn't pull very hard its bit like turbo lag it will accelerate and go through the rev range but not as strong or quick as it should. And often then when changing gear it'll pop or bang and jolt then again in next gear it doesn't pull as hard as it should. Thing is it only happens sometimes and other times it'll pull fine and accelerate as it should, also this only seems to happen in normal mode when using the sports mode the car runs fine everytime and pulls hard in all gears from all revs and never has any issues.... The car has recently had a new rear o2 sensor, turbo actuator, and front boost solenoid, and new spark plugs. Car has no warning lights on and nothing showing up on diagnostic. I can't think of what might be causing the problem and why it's only affecting normal mode and only occasionally, Anyone got any idea's / advice ?
