(2 pack) Cataclean Fuel & Exhaust System Cleaner, Automotive Additive, Catalytic Converter Restorer, 16 oz

Works. Had about an 1/8th of a tank of gas, Put in 10 worth of premium gas drove a bit over 50 miles. When I got home I cleared the code, I have a code reader. They are cheap and easy to use. Drove for a while then. worked. Will put about half a tank of premium next gas stop

This stuff really works. I was stressing from driving with an expired inspection sticker because every time I shut the light off it would come back on within 20 miles. I read about this and gave it a try. I followed directions and put over 100 miles on to clear the codes. It PASSED inspection. That was in march. It is now September an still no 02 sensor code.

Was starting to smell sulfur and immediately thought of my cats being clogged. Saw this on line, read good reviews. Put it in my SUV and after a couple of days no more sulfur smell

This was a lifesaver for me, it took awhile to work but it had to clean things out. The car is not jumping the rpm. I still have the code but I have not tried to have it removed apor get a smog yet. Here is hoping I pass.

My car had been throwing codes about the catalytic converter, so I did some research and this cleaner was suggested to use before I replaced the converter. Since I used it I have had no more codes.

SO FAR GOOD I PUT IN MY CAR GAS TANK WHEN I HAD AROUND 5 GALLONS 93 GAS FROM SHELL GAS STATION I DROVE ALMOST 47 MILES AND STOP IN PARKING LOT BUY SOMETHING FROM STORE AND START MY CAR CHECK ENGINE LIGHT WAS GONE NEXT DAY I FILLED 93 GAS FULL TANK FROM SHELL GAS STATION IT'S EXPENSIVE BUT I HAVE NO CHOICE I DROVE AGAIN AROUND 20 MILES SO FAR I DROVE AROUND 150 MILES CHECK ENGINE LIGHT IS NOT COMING LET SEE.......................

Had the infamous P0420 check engine code and it was time to renew the vehicle registration with smog check certification.....Used Cataclean per the instructions...check engine light extinguished......passed the smog check certification..... vehicle registration renewal accomplished. 🙂

I don't know if I would recommend this product yet, because it did not seem to do the job the first %26 only time that I have used it, but I understand you have to repeat its use to actually see it work. It was recommended to me to use it to clean out my catalytic converter so my check engine light would go off and it would stop coming on and telling the computer check that it needed to be fixed or replaced. So I plan to use it again as recommended by the manufacturer and then I will give it another review.

Worked for about 3 days. Initially check engine light came back on the 2nd day of use. Then after driving for about 50 miles the check engine light turned itself off and stayed off for about 3 days before it turned back on and stayed on. Maybe a quick fix to pass an emissions test but not worth much beyond that.

I've been the original owner of my 2016 Subaru WRX (FA20DIT, ~108k miles) since day one. It's been meticulously maintained, never abused, and has run flawlessly—until the day I used Cataclean. On August 23, 2025, I followed the product's instructions to the letter: • Added Cataclean to my tank at ~1:15 PM with just over 3.5 gallons of fuel. • Drove to a nearby station, refueled at ~1:30 PM (receipt in hand). Within minutes, I noticed an odd sound. Minutes later, just past my exit on I‑75, the engine lost power and developed a violent knocking noise. I had to pull over and get towed home. A trusted ASE‑certified mechanic diagnosed rod knock and a spun rod bearing, with likely block damage. His verdict: rebuilding would be pointless—$12,000 for a full engine replacement was the only viable option. This catastrophic failure happened immediately after using Cataclean. This wasn't a coincidence. This was a direct, immediate, and devastating failure following the use of their product. For a company to market something as “safe” for gasoline engines, then leave customers holding a five‑figure repair bill when it grenades their motor, is unacceptable. If you value your engine, your wallet, and your sanity—stay far away from Cataclean.