Hey Guys I just picked up an used GL450 and everything seemed just fine. My brother filled it up with 87 on accident but I didn't think much of it cause I have read many others have done that before. I didn't know about the shifters behind the steering wheel and later that evening I accidentally shifted the car to D7. Almost immediately when it shifted the check engine light came on and the code was 0432 Main Catalyst Efficiency Below Threshold Bank 2. I haven't noticed anything while driving and its not driving sluggish. Is it possible the 87 gas threw the cat off or maybe the quick shift?