GUARANTEED TO PASS EMISS.

A fruend called me anout her MIL/Enginel light coming on. P0 420 came on i think. O2 sensor bank 1. Exhaust had good pressure so catalytiv wasnt plugged up. So bought some of this and her light went out i assume bevause she said its ok (shes vietnamese with not the best English) and hasnt mentioned it in last 3 weeks. I bought a few more to give her some for next time when needed and for my 09 small truck.

It has worked every time I've used this product. Won't fix a damage catalytic converter but will help you pass the test if your car almost passed.

The engine check light disappeared for two days and came back. Before every time I reset the error code the engine check light would not come back before few days, but after using this product the it would come back next drive.

Used it as directed. Down to an eighth of a tank. Poured it in and added enough gas to get back to one half a tank. Wanted to get it mixed in really well. Immediately jumped on the interstate and ran 75 MPH for 40 miles. Stopped and filled the tank and when I restarted the engine, the light was off. Coincidence? Not a chance. Light had been on continuously for weeks. AutoZone said I needed a catalytic converter. Nope. One thing I found out the hard way. If your gas filler has a flap at the top, make sure it is easy to push aside. Mine had a little release button near the top that the filler hose would depress before the flap would release. Dumped the first bottle right on the ground. Twelve bucks wasted. No one to blame but me, I guess. Still a bargain, even at twice the price.

Simply, absolutely works. Your car will run great again with increased gas milelage too.