Cataclean Fuel & Exhaust System Cleaner for Gasoline Engines, 8 oz

I guess it's surprising that the product works as advertised, but this stuff cleared a P0420 code on my Buick when I used it as directed. Follow the directions and keep your fingers crossed. I would definitely recommend this to anybody with the above code. $28 beats a $1200 catalytic converter replacement every time.

Check engine light came on. UGH Who doesn't feel their stomach drop when that happens. Add to that it came on about 3 weeks before we were due for inspection in order to renew our registration. Double UGH! So we have it coded at the local auto supply place and it comes back to Catalytic Convertor. I call around and the price to swap out the convertor is about $2000. A simple further diagnosis was going to be about $200 before anyone would work on it. Its an older car and it wasnt unexpected. We have the money to fix it and while no one really wants to spend $2000 on a car repair .. you drive an older car and things happen. Our problem was .. it was a really really inconvenient time. We would have to rush to get it done in time for the registration renewal which would mean getting a rental car and more in order to go to work and not take the time. it was just bad timing and not finances that made it awful. So .. I will admit .. I didnt give this liquid magic a snowballs chance in &*^% of working but the wife said .. for $40 for the 2 pack lets give it a try and we can replace what needs replacing later. Fine honey but I think its throwing $40 bucks away. I used it as directed on a Saturday and then used the second bottle on the following Saturday and reset the computer. Drove it for about 9 days and no check engine. WIFE BROUGHT IT TO DMV TODAY AND IT PASSED INSPECTION!! Probably would have worked fine with just the one bottle but I figured since I was throwing money away might as way throw away more. Trouble is .. it wasnt throwing money away .. it just saved us about $1950 plus rental car costs and lost time from work. Product is AMAZING! Now we can take a little vacation time and address the problem without feeling rushed. Awesome stuff. Buy it

Here's the quick summary: Yes I used this and yes my car passed smog test.... but I would try lots of other things before using Cataclean again. My vehicle is a 2004 Toyota Sienna with 137,000 miles. Check engine light (CEL) has been on for two years now. The CEL is on due to the following codes P0420 - Cat Bank 1, P0430 - Cat Bank 2 , P2238 - AF Sensor Circuit. This year we got the registration renewal and were required to get a smog certificate. Since you can't pass smog test with CEL on, we took the van to the dealer to see about getting it the CEL fixed. The dealer recommended replacing both catalytic converters the A/F sensor and calibrate ECM. All for a cost of over $2,800. So instead of spending the $2,800 I figured it was worth it to give Cataclean a try. I followed the directions and added the entire contents to about 1/4 tank of gas. Then immediately drove the van until it was empty. The van was not completely empty, but the yellow fuel warning light did come on and the gauge was on E. At this point I filled up the tank with premium gasoline. After filling it I immediately drove the van for about 40 miles. I was expecting the CEL to turn off but it did not. At this point my story gets less normal than most I suppose. My wife drives this van most times and I have another car. It just so happened that my wife was sick with a bad case of the flu and she did not drive the Sienna for more than 1 week. So the Sienna sat with nearly a full tank of fuel and whatever was left of the Cataclean for 1 week. After 1 week of sitting in the garage, I decided it was time to try to drive the van and see if the CEL would turn off. This is where it gets very weird and discouraging and expensive. I pulled out of the garage and the van barely ran at all. It felt like only half of the engine was running. The engine had very little power and to make matters worse the CEL was now flashing ON and OFF. I pulled over and did some quick research on my phone and found out that a flashing CEL is bad news. I spent the next 4 hours "babying" my car. I would drive it for a little bit and the CEL would flash. So I would pull over and let it idle next to the curb. When the engine was simply idling the CEL would not flash. I did this for hours and hours and the CEL flashing got less and less prevalent. Finally the CEL stopped flashing after about 4 hours of driving and idling. If this does happen to you, you need to be very careful. Driving with a flashing CEL could lead to really expensive damage and even your car catching on fire. After that long evening of babying my car, the CEL never flashed again. But the car did not run correctly after that either. The car was rough at idle and vibrated a lot while it ran. And now, my car had a new code P0354. I took it to a mechanic and he replaced the #6 ignition coil and spark plug and cleaned the fuel injection system. This made the car run smooth and cleared the P0354 code. Replacing the ignition coil spark plug and cleaning the fuel injection system cost $510. I had a lot of expensive problems after I put in the Cataclean (see above). These problems could have been a coincidence and I could have had those problems without the Cataclean. After all, it's an old vehicle with lots of problems. Anything is possible. But I don't think I will be using Cataclean again. I cleared all codes and tried to run the monitors. For those of you not familiar, there are "monitors" which run in software on your vehicle. These monitors must be run and passed with no codes before you can have your car smogged. If the monitors generate codes, then the CEL turns ON. If you clear the codes, your CEL does go off, but your monitors are now "imcomplete" in your cars OBD memory. You cannot pass smog with incomplete monitors (actually the number of incomplete monitors allowed to pass smog varies from state to state so check with your motor vehicle department). You can find the rules for California here: [...] So now my car runs smoothly, the Cataclean has run through the emission system and the CEL is off. I have two incomplete monitors. One of the incomplete monitors is the Catalytic Converter monitor. So I then drive the van around town running some errands. Mostly stop and go, but some highway driving. After about 50 miles the CEL turns ON and generates code P0420... very discouraging. But I did not give up. I cleared the P0420 code and decided to try nothing but highway driving at moderate speed. Just a hunch I guess. So I got on the freeway and drove. Entirely freeway driving at very moderate speed. I got in the slow lane with the trucks and probably averaged 55 MPH and for it's worth I turned my Air Conditioning off. I did this for about 75 miles. I kept checking the scanner to see if the monitor for the Catalytic Converter had run, but it said incomplete. I must have checked the scanner 30 times to see if the monitor had run. Then it happened, the Catalytic Converter monitor ran and the status went to OK with no code. As soon as the monitor ran with no code I found the first smog station I could find and got a smog certificate. YEAH!!!! In order to do all of this I needed an OBDII scanner with me in the car to check monitors, read codes and clear codes. I used a very inexpensive OBDII scanner that I bought at Wal-Mart for $21. I think some of the inexpensive models offered on Amazon would work as well. You don't need an expensive scanner to do this. The main thing for checking monitors is a feature called "I/M Readiness Status"-- make sure your scanner can do this function. So did the Cataclean help pass smog? Did Cataclean cause the damage to the ignition coil? Did not driving it for a week in the middle of this process cause a problem? .... I don't know. If I were to ever need to use Cataclean again, I would drive the vehicle... a lot and try to get it through the system as quickly as I could. Hopefully, I won't need to use it again.

Great Story. I have a 2003 Toyota 4Runner with 217K miles on it. I am trying to sell it and the one thing holding it back is the check engine light (CEL) with the code P0430 (Catalyst System Efficiency below threshold Bank 2). I have had it checked out and of course the repair shop "oh you need a new catalytic converter on the passenger side...there is some nasty stuff coming from the exhaust." blah blah blah. I even told the guy to check the 02 sensors if at all possible and that I was selling the car and I wanted to avoid spending a ton of money. They never did check the sensor, but they were more than happy to charge me a cool $115 to tell me what I already knew. Long story short, I put 2 cycles of Cataclean in and I passed the emissions inspection yesterday (never thought it was possible!!). Now, I can tell you that the CEL will stay off for about 60 miles or so then it comes back on. So it did not fix that issue like some of the other reviews (I just unhook the negative terminal for about 10 minutes or so and get it to reset). However, I firmly believe that this stuff did do something to clean out the fuel and exhaust system enough to get it to pass which is the ultimate goal. I think it is safe to say that there is absolutely nothing wrong with the Cat and I can attribute the CEL to a bad sensor. I would think the emissions testing facility would have caught the cat whether the CEL was on or not. Words cannot express my disappointment in the repair shop that gave me the diagnosis of a bad cat. Bottom-line, give this stuff a try. It may not turn your Check Engine Light (CEL) off but it will do a good job of cleaning out the system (as advertised) and possibly help you to pass the emissions test. I did follow the instructions and ran it all the way down to below a 1/4 of a tank, put the Cataclean in, drove it for another 20 miles and then put in premium fuel. I did 2 cycles of that back to back. I could even tell the MPG improved. I am getting 19.5 on a V8 4Runner with 217k miles on it. Hope this story helps!

I got my year2000 lexus es300 check engine light (CEL) on and code is P0420, the car got 185K miles already, my inspection is coming, What I do? change a OEM catalyst converter cost me $2000. Check amazon reviews, I got this one and poured it in base on instruction. Did not work for the first 10 miles with 1/4 tank, CEL back again. After refilled the gas tank, I deleted the CEL but it back on again after 50 miles, I deleted again then it back after 100 miles. I gave up and even want to buy all parts(O2 sensors and catalyst converter), but finally it works after 150 miles, Code P0420 are gone and CEL never back on. I went to MVC and Passed inspection, Binggo! Now it is more than 200 miles and still no light on. I am so happy with this product, it is not just clear the CEL, also clear the whole fuel systems, make my car runs so smoothly. I had rough idle, it make it much better now. Gas milage is better too and engine is so smooth now, like new one. I highly recommend this one and will use it again for another few months. -------------------------------------------------------------------------------- Update: After I passed the inspection and drove about 300 miles, the CEL back again, it did not really fix the CAT issue but it does help me get passed the inspection. Before, the CEL back on only in 20-30 miles, now, hundreds miles. I reduced it to 4 star since it did not help to fix the CAT problem permanently, but it did help me passed the inspection, which is much more value than $25. so for me, it is still worth to buy and try. --------------------------------------------------------------------------------- Update2: I fixed the P0420 issue, it is due to bad O2 downstream sensor,. I just replaced the down sensor for $50 (part)+ $50(labor), it fixed all, P0420 code are gone, so it is not CatClean not working but O2 sensor issue. you are not expecting Catclean can fix O2 sensor electronic issue, but it did make my idle very smooth and make the CEL on delayed, so I still bring it back to 5 Star. Hope this feedback can help others who can not cleanup code with CatClean. If your code not disappear, mostly O2 sensor issue or Cat leaking something....

I'll try to make this brief. I used Cataclean once about a year ago on recommendation from a mechanic and various online sources as a stop-gap measure to keep the engine light off for enough miles to pass inspection with a P420 catalytic converter code. This also required turning off the light with an OBD scanner first, adding the Cataclean, then driving over 100 miles and resetting the I/Ms. It was successful, but I can't say if the product helped keep the CEL off or if it just happened to work out. After inspection, the CEL returned at 280 miles, which it always will, this is not a permanent fix, please understand that. Now comes the very, very bad part. This year, each time I turned off the CEL to see how long it would remain off before inspection, it came back on well before 50 miles. So I know my catalytic converter is getting worse, no way to make it one more year, it would have to be replaced. But I thought I'll give Cataclean one more try and maybe it will help keep the CEL off a bit longer before I commit to $2,000+. Cleared the code last night. Added the Cataclean, precisely as directed, 1/4 tank, etc. Started driving. Within ONE mile, massive misfires, chugging, struggling, no pickup, CEL FLASHING. I had entered a highway on ramp when it hit, managed to get up to speed at least, then exited immediately. Vehicle shaking and sputtering at stops, I put it into neutral and gave it some gas so it wouldn't stall. Drove to the nearest gas station and filled the tank to at least dilute this garbage, the best option at the time. I ran my OBD scan at the gas station, P0300 random misfires code, all cylinders reporting misfires. Cleared the code so I could see how fast it would return. I drove only around my neighborhood so I wouldn't be far from home if catastrophe struck. The CEL of course came on again in a few miles but the jerking, stuttering, shaking and struggling were greatly diminished now because I diluted the additive with premium. The problem remains, however. When the CEL came on again, at the very least it was steady and not flashing, certainly because of my quick thinking to dilute it. Now I'm in the unenviable position of HOPING it's JUST the catalytic converter that got badly clogged from the release of filth or whatever the product released into the system in the single mile I drove it after adding it to the tank. Did the research online. It could be a lot of system components affected in addition to the already weak cat. Look it up yourselves, PLEASE! This can foul your spark plugs, fuel injectors, O2 sensors. It can severely damage your cat when you have misfires, causing it to overheat and break apart. There are tons of articles about all the possible side effects of using this. I never came across them when I researched it the first time because I didn't specifically search for these side effects. All I saw were opinions that maybe it will work out, maybe it won't, but that it was safe. THIS IS NOT A SAFE PRODUCT! Look, maybe it's OK for some people - it doesn't work at all for others. A very mildly dirty cat might be cleaned enough to get through an inspection and turn off the CEL for a while longer than normal but - wow. Did I ever make a huge error using this again. Yes, nothing happened the first time I tried it. You might get lucky. You also might release so much gunk into your engine and exhaust that you destroy your vehicle to the tune of THOUSANDS. Do the research. Be smart. I poured this junk into my tank without a care in the world, thinking it would either help keep the CEL off or not and that would be it, never suspecting massive misfires and a flashing CEL. It's a holiday weekend now and I can't get to a garage until Monday. I will update this review when I learn the extent of the damage and I'm hoping it's only 2K for cat replacement. Imagine that. Think long and hard about trying this. I hope I can save some of you from the scary situation of being on the highway and misfiring and struggling to get up to cruising speed and a nerve-wracking drive back home or having to call for a tow. Consider this a public service. Get online, find out everything about this and other additives before using them!

Useful for newer catalytic devices but will not get a old/crack or broken unit to work.

I followed the directions on the bottle and added a dose to the tank before filling up. The instructions were straightforward, and I didn’t need any tools or extra setup. I used one bottle for the first treatment and kept the second on the shelf for later. On a drive across town with a stack of proofs in the back, the car felt like it was running normally, with no new hesitation or odd smells. I can’t say from one treatment whether it cleaned the catalytic converter or changed emissions, so I’m waiting for the test rather than making a bigger claim. Still, I was glad I had it on hand when the checkup got close. It was easy to fit into a regular fill-up, and having the second bottle ready saves me from remembering to reorder right away. For me, that’s a practical bit of maintenance for a car I rely on for studio errands.

Vi buenas reseñas en internet, apenas lo coloqué y esperemos sirva. No ha vuelto a salir el error P0421, lo usaré regularmente.

I think the Cataclean did help. The fuel economy has improved and so far so good no error message has re-appeared appeared.

Je suis extrêmement satisfait de l'efficacité du Cataclean 120007 Nettoyant complet pour moteur, carburant et système d'échappement. Cet ajout simple à ma routine d'entretien automobile a eu un impact significatif sur les performances de mon véhicule. Dès la première utilisation, j'ai remarqué une amélioration notable de la réponse du moteur et une réduction des vibrations indésirables. Le nettoyant a agi de manière rapide et efficace pour éliminer les dépôts dans le système de carburant, améliorant ainsi le rendement énergétique de mon moteur. Ce que j'apprécie particulièrement, c'est son action complète sur l'ensemble du système, y compris le système d'échappement. Non seulement il a contribué à réduire les émissions, mais il a également rétabli l'efficacité du catalyseur, ce qui se traduit par une conduite plus propre et respectueuse de l'environnement. L'application du produit est simple, sans nécessiter de compétences mécaniques avancées. J'ai suivi les instructions fournies et constaté des résultats probants sans effort supplémentaire de ma part. Un autre avantage notable est que le Cataclean 120007 est compatible avec une variété de moteurs, ce qui en fait un choix polyvalent pour les propriétaires de différents types de véhicules. En résumé, je recommande vivement le Cataclean 120007 à tous ceux qui cherchent à optimiser les performances de leur moteur et à prolonger la durée de vie de leur système d'échappement. C'est un investissement judicieux pour un moteur plus propre, plus efficace et une conduite plus agréable.

Dealer diagnosed that my catalytic converter (Infiniti 2009 with 210.000 km) has to be changed. They turned off Check Engine Light; it came back after 3 days. I bought this product, put 1/2 in a full gas tank, drove till empty then did it again with another full gas tank with the other half. About 1/3 of the second tank, Check Engine Light disappeared. The engine seems to rev quicker, cleaner and the car picks up faster. It does work.

Actually reduces emissions and helps pass mot. Wouldn't use it as a CAT or general cleaner though as it didn't get rid of the CAT efficiency P code and it doesn't contain any polyetheramine(PEA) that other cleaners use which is the only thing proven to clear carbon deposits.