Wow, they are not very smart are they, but then again, not many MB dealer SA's are. All Shell gasoline meets the "Top Tier" standard, so there's absolutely no reason that a car should run poorly solely based on using Shell gasoline. So their answer is to make an attempt to void your warrranty by making you use unapproved fuel conditioners and regular gas, brilliant, that's all I can say, brilliant.
It's very simple, go talk to the service manager, and tell him you got disturbing advice from the SA and you want him to assist you setting up a meeting with the MB Zone rep regarding that dealerships recomendation to fix an engine warranty issue by running regular gas instead of premium and to use fuel injector cleaner not recomended by the owner's manual and since this may impact your warranty, you just want to make sure MB is on board and see if there's any technical bulletins that recomend this and before you do anything, can they put this in writing on their letterhead so if MB rejects a future claim because of this advice, they have recourse against the dealership and it's management.
You have to understand how warranties work to appreciate what they are trying to do. First, MB pays a lot less than you do for repairs. Mechanics are paid based on shop hours billed for a job. So say the MAF is bad, MB may pay for 30 min labor to replace the MAF at $75/hr and you may pay 2 hours labor at $125 an hour so if they are busy, which job would a mechanic want to do? Then factor in the SA's usually get 10% commission, which job would they prefer to do? So many times, warranty work takes a back seat, especially if they know you will bring your car in 2 months from now and pay them bigger bucks.
So how can you beat the system? It's called the Clean Air Act, if there's a situation that violates this act and they knowingly violate it, they can get fined big time, so that little light on your dash, the check engine light, that's one bugger they can't white wash and ignore, why, because our government takes it seriously. How do you get that light to shine bright and proud. Start your car, disconnect as many connectors as you can and let it run and then connect it back up when the light comes on. This will throw so many codes, your car's engine will get a lots of attention. If they do nothing but reset, do it again, haha. Look at it this way, no matter what happens after that, you are covered because you can say 6 months later that you got this code before and they didn't fix it properly.
I know, in a pefect world, getting warranty support from your dealer is expected, but that's just fantasy nowadays.
But tell them there's a hesitation but if they can't find anything, pull the connector on the maf, run it for a few minutes until the CEL comes on, then plug it back in and bring it in, haha, then they have to run more tests.
