I just bought my lincoln ls yesterday and it was working really good but i put regular gas in it not the premium and it started acting up on me, it started backfiring really bad. what can it be? the floater, filter or the fule pump? please help me!

It's the gas. That vehicle was designed to work with 89 Octane Minimum which is the mid grade in most areas. The high octane is usually 93 but the low octane or regular is normally about 87 octane and that doesn't work well in that vehicle. You have a few choices. Drain teh tank and put the proper fuel in the vehicle, Get a bottle of fuel injector cleaner and if you are below a half tank fill it up with High grade, 92 or 93 octane, or get a bottle of octane booster and fill the tank up with mid grade or better fuel to run out that low grade fuel that is giving you problems.

All you need to do is to use the right fuel gas grade for your car check the manual it will tell you not all cars take any tipe of gasoline youll be fine just use the right grade.

Luxury cars often call for premium gas because they have a higher compression ratio. You can ruin a porshe motor by running the cheap stuff! Get 2 bottles of octane booster, any brand should work. Dump them into your gas tank and let it idle until it smooths out. My wife's blazer will kick the check engine light on if she buys the wrong stores gas. They are not all the same, and my guess is you will have to shop at different chains to find a blend your car "likes"