Using Regular vs Premium Gasoline in VW Passat



I just purchased a 06 VW Passat and the dealer told me I could use regular gas - instead of the suggested premium. He said as long as I add one bottle of Techron for every 5 fill ups. He wasn’t a VW dealer - am I going to wreck my car?


I would read my owner’s manual carefully. If premium is required, then use it, especially during the warranty period. If premium is “recommended for best performance”, then the statement is merely a recommendation, not a requirement, and you might want to try regular. I would keep records to determine if there were a performance or mpg difference in the two, and then choose the optimum fuel.

I believe the Techron use is too much for that car. My Ford truck dealer, who has no axe to grind on fuel additives, recommends Techron one a year per vehicle, for preventive maintenance purposes. I believe that is a prudent approach. Your non-VW dealer recommendation adds 1.25 or more per fill up, which may then make the cost of regular plus Techron cost more than just using premium only.


That’s been an ongoing topic on VW Forums . If you use regular you lose mileage and performance . As far as cost the loss of mileage negates any saving ! It’s not like regular is a buck cheaper than premium !


As long as the engine isn’t pinging it should be OK. But that could change day to day. You could have more people in the car…or climb more hills certain days…these all affect the load on the car, thus if it will ping. As long as everything is working correctly the pinging should be controlled…but you will see a decrease in performance and gas mileage. How much…not really sure. I don’t know what the Techron is going to do for you. All Techron is…is a very good fuel system cleaner. Regular gas from one station is probably just as clean as it’s premium.


That bottle of Techron, good stuff that it is, used every 5 fill-ups will eat most of the savings in gas costs. It’s also totally unnecessary- regular gas has the same amount of detergents as premium.

As already noted, the drop in fuel economy will make using regular more expensive than premium even without the Techron. That’s assuming VW recommends premium to begin with. If VW says it’s REQUIRED, you use regular at your engine’s peril. Severe engine damage is possible.


The dealer seems to be under the incorrect assumption that the premium has a better additive package. The gas companies a long time ago used to put better additives in premium to get people to buy premium gas when their cars didn’t need it. The FTC made them stop this and now the ONLY difference is the octane, which is a measure of the gasoline’s resistance to detonation and thus suitability for running in high compression and/or turbocharged engines. It has nothing to do with the energy content of the fuel or its ability to keep your engine clean.


I had an 03 Passat which I recently sold. I bought it from a VW dealership and was told by the service department to fill up with regular gas and not premium. I drove that car for 4 years and never once had a problem with it. I once asked my mechanic what he thought about fuel additives. He said, “Put a bow on a pile of poop and someone will buy it”.

The owner's manual will say that it must have high octane or that it may use regular but should use high octane.  The parts the leave out are:
  • If it needs high octane, using regular can damage the engine.

  • If it should use high octane then it has a system to sense the low octane and to make adjustments to the car that will protect the engine. However the adjustments will result in lower mileage (reducing or wiping out any economic advantage) and will reduce the power, defeating the reason most people buy cars that require high octane.

  • Using high octane in a car that does not recommend it very very seldom causes damage but cost you more.


VW definitely recommends premium fuel in all the Passats. In Colorado, premium is only about 5% more expensive than regular. The difference (in %) is even less in California because the price of regular is higher, but the difference between regular and premium is still only about $.20. I think you will find this true just about everywhere you go. You will see more than a 5% drop in mileage by not using premium. So, why bother?