Regular or premium? BMW 328 i X drive

drjcool1

Hi to all!

I am in the market for a 328 i X drive. I previously had a 2006 X3 which I liked very much. Although I began using premium fuel, I was told by several people including my salesperson, that using regular would not hurt the engine and the reduction in the performance is usually not an issue. So I switched to regular. While my gas mileage may have dropped a bit I not perceive a significant reduction in performance. The savings were significant even with the slight drop in gas mileage.

What is the experience of those folks using regular gas in the 4 cylinder turbo in the current version of the 3 series? Let's have a discussion and I would appreciate pros and cons and all reasonable opinions.

Thanks to all!

busiris

The most obvious thing I see is that in general, premium fuel contains additives and detergents that are often not found in regular grade gasolines.

As for what/how much impact that would have on an engine designed to run on premium, but instead run on regular, I could only speculate.

Personally, I will follow a manufacturer's recommendation over a salesperson's every time, unless the salesperson can factually demonstrate his claim has merit.

In the end, just because you get 10K, 20K or more miles without any visible issues surfacing doesn't automatically translate into no increased costs/maintenance/repairs down the road.

Of course, your experience may be different...

rugbyman

I'm waiting for my 328i, delivery expected Nov. The manual indicates 91 octane minimum. Turbo engine cars usually need higher octane to prevent detonation. Modern engines have knock sensors that can reduce timing when knock is detected but I will run 91 octane or 93 if 91 is not available. Nothing to do with quality etc, just the higher the octane the better knock protection it provides. Knock or detonation can damage the pistons or bend the connecting rods, in severe cases, under high load and slow engine speeds.

clachnit

Edmunds has a good story on this topic Save Money and Stop Buying Premium. The trick is to know whether premium is merely recommended for your car or required, and the story has a link to both lists for current model year cars--very handy. For my 2011 BMW 328i, premium is required. So although I'm a cheapskate, that's what I buy. I just look for bargains on premium, using grocery-store usage points at good-quality brand stations.

abram_h

The trick is to forget the increased price of the premium fuel. I just bought a used 2011 328 xi and the initial shock of paying extra every time has worn off. Stick with the premium.

kyfdx

@abram_h said:
The trick is to forget the increased price of the premium fuel. I just bought a used 2011 328 xi and the initial shock of paying extra every time has worn off. Stick with the premium.

Total agreement. Premium is only a waste of money, if the car isn't designed to take advantage of it. Put premium in your BMW and never think about it, again.