Took My oil burner for it's MOT last week and it was that good on the smoke test it would not register! 0.01 at idle 0.03 at redline. The gas machine said it needs to be revved and wouldn't accept the test! How mental! Failure due to being too good. Got around it in the end but doesn't the test needs changing for cars with a DPF!!. Good reason to get get it took out in my book!!