Nothing happens, except your wallet will be lighter.
When you mix regular unleaded fuel and unleaded plus fuel in a gas tank it results in a mixture of fuel with an octane rating higher that regular unleaded fuel but lower than the octane rating of unleaded plus fuel.
You get a lower gas mileage because it needs more fuel at one time to reach the maximum potential, and it still doesn't have very good performance.
regular gas IS unleaded...
Regular unleaded gasoline.Regular unleaded gasoline.
The 2009 Lincoln MKS runs on premium unleaded (recommended).
The 2011 Lincoln MKZ runs on regular unleaded.
you will be ok MIGHT notice a very s;ight decrease in performance
Regular unleaded.Regular unleaded.
regular unleaded.regular unleaded.
You will risk doing damage to the catalytic converter(s).
The 2012 Lincoln MKT runs on regular unleaded.
Regular unleaded.Regular unleaded.