Probably normal, though I remember witnessing a real lightshow out the tailpipe of an old A1 jetta n/a that was refusing to blow up. (19mins full throttle, no oil or coolant. Just kinda slowed down and stopped. Started again 1/2 hr later and drove it 10 mins to the wreckers. left it at full throttle in the parking lot and went home!)
a good long twatting