DURA LUBE Severe Fuel System Cleaner | 16 oz., Single

This product shuts off my engine light when it indicates catalytic converter. The truck works great and passes smog checks with ease. I'm comfortable using this product every 6 months or so especially that it seems to satisfy whatever issue turns on my check engine light.

I used this on my wife's 2008 Honda Civic Si (150k miles), and the hesitation/rough acceleration problems, and engine pinging/knocking noises under acceleration were resolved within the first 10-20 miles after using this. I also used it in my 2017 Honda CBR 1000RR motorcycle for similar problems, and I experienced similar positive results! I will continue to use it as part of our vehicles regular maintenance.

I had an engine light on that was related to catalytic converter. I used the additive as directed and the light went off. I continue to use this product.

Great product used it for years but I switched to Sta bil 360

My 25 year old Chevy was cranking, sputtering, and backfiring every time I went to start the car. Once I got the car running, it took a while to get power during acceleration. My mechanic said it could be either the fuel filter or the check valve on the fuel pump and that I would have to make plans to leave the car and it would be expensive to repair at $120.00 per hr labor + cost of parts. I decided to try a fuel additive instead. I ordered Dura Lube HL because it said it was twice as strong as other additives. After I added it to my tank, it only took about 5 minutes of the engine running before it came back to life. It now runs like a brand new engine. Thanks Dura Lube!

I've used this product for years in all my vehicles, including my 2001 Dodge Intrepid R/T. Without hesitation, I put a bottle in a full tank of fuel after every oil change, (3K-5K) to maintain the entire fuel delivery system from the fuel pump to the injectors. Though my car has over 184K miles, the 3.5 V-6 H.O. engine runs smooth, idles quietly and accelerates hard as if she was still new...I truly believe in the effectiveness of this product, as well as the DuraLube Engine Treatment product. It also is noteworthy, to know the brand was founded in 1986 and the corporate office is still in Gahanna, Ohio....it's truly a first-class American-Made product, your vehicles best friend for longevity of its fuel system operation along with improved fuel economy and performance as the result...bravo!!

Two bottles of this stuff and my check engine light PO420 error came back. Does not seem to have any effect on the catalytic converter

I had the engine light come on; it indicated my catalytic converter was clogged. I researched it and it suggested replacing it or to try one of the liquid cleaners. I tried a couple, but the light came on again, repeatedly. I tried DuraLube and I he light hasn’t returned.