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🚗 Clean fuel, clear conscience, and a ride that’s ready to impress!
Nitrox Catalytic Converter Petrol Cleaner (500 ml) is a powerful liquid formula designed to clean carbon and resin deposits from your engine, fuel, and exhaust system. It improves fuel efficiency, reduces harmful emissions, and helps vehicles pass MOT emissions tests with ease. Easy to use by pouring directly into the fuel tank, this cleaner restores engine performance and prolongs engine life, making it an essential maintenance product for petrol vehicles.









| ASIN | B091Z28593 |
| Best Sellers Rank | 2,168 in Automotive ( See Top 100 in Automotive ) 92 in Fuel Systems |
| Brand Name | Nitrox |
| Contains Liquid Contents? | Yes |
| Customer Reviews | 4.3 4.3 out of 5 stars (566) |
| Included Components | Nitrox NPC500 Catalytic Converter Clean Cat Petrol Fuel and Exhaust System Cleaner 500ml |
| Item Form | Liquid |
| Item Type Name | System Cleaner |
| Item Volume | 17 Fluid Ounces |
| Item Weight | 0.5 Kilograms |
| Manufacturer | Tetrosyl Limited |
| Material Features | Unscented |
| Number of Items | 1 |
| Scent | Unscented |
| Specific Uses For Product | Automotive Exterior |
| Surface Recommendation | Autmotive Exterior |
| Unit Count | 500.0 millilitre(s) |
A**.
Excellent product if emissions too high during MOT!!!
My 11 year old Skoda (petrol) failed its MOT based on emissions, which were way too high. The garage already replaced the Lambda sensor etc and although this brought down the emissions, they were still too high to pass the MOT. Nothing else was visibly wrong, there was no engine/ catalytic warning light, no exhaust or engine noises or visible fumes, no burning smells etc. Garage said to take it to a main dealer for a more in-depth diagnostic as they couldn’t put their finger on why emissions were still so high. However, before I went down that route, I decided to get a second opinion from another local garage who suggested to try a catalytic cleaner, give it a good run out on the motorway (50 miles each way) and fill up again with 98 octane petrol (rather than the 95 octane/ E10 stuff as that apparently causes more carbon deposits and blockages in the catalytic converter and exhaust system than the previous 95 octane petrol, which can lead to higher emissions). Second garage said that if there was something wrong with the catalytic converter and the car needed a new one (£1,000 upwards), then it would definitely show up via a warning light and/ or during the diagnostics stage, so that was probably not the problem. Anyway, bought the Nitrox Catalytic Converter Cleaner Petrol via Amazon based on the good reviews from people with similar problems to mine and did as suggested by the second mechanic/ instructions as per bottle – AND IT WORKED! Car passed its MOT the second time round, with no emissions issues at all! My tank was ¾ full when I put the cleaner in, then went for a 100 mile round trip down the motorway, used up a bit more petrol commuting to work for a couple more days, booked another MOT three days after the motorway trip and it passed no problem. Extremely happy with the product and the advice provided by previous reviewers and will keep this in mind for next year’s MOT. Will also start to fill up with 98 octane petrol from now simply to prolong the life of the engine/ car – 11 years is not that old after all. As previous reviewers have said, give it a try before you fork out for expensive repairs on your exhaust system and/ or catalytic converter, especially if there are no engine or exhaust noises or fumes and the car is otherwise running well.
J**E
Impressed
Works well seems to improve fuel
C**Y
Excellent service,great value.
Speedy service
G**E
Worked when Cataclean didn't
I've always had an engine warning light on with my petrol corolla verso. I've used cataclean and had the light go out for a few miles, but not reliably. Had my mot coming up and put this in the quarter of a tank that it suggests. Didn't wait for it to clear but reset the warning light with my odb2 reader. Drover it around town for about 20-30 minutes, couldn't do motorway speeds or high revs and in that time it didn't come on. Took it for it's mot, and where we've cleared the light before but it still fails emissions, it sailed through the emissions part. TWICE!!! (it failed on failing uv joints first time!). I'd use it again. It's cheaper than cataclean, and I will add to this review after I've done more miles to see if it lasts.
I**D
Didn't notice anything
To tell u the truth I didn't notice anything that help my car,catclean is much better
S**V
Worked a treat
I was a little sceptical that this would work. My VW Polo had thrown up a warning light connected with a CAT sensor; given the spiralling costs of garages, I decided to give this product a go. It completely resolved the issue, after I cleared the engine warning light, it has not returned in the last 3 months and if it did I would buy this again. Really noxious smell, so don't leave it in your home for too long - be warned!
N**N
Very good
Very good
R**N
Good value for money
After using this I noticed a difference, the bottle is designed well and ensures no leakage. Useful if you’re trying to clear engine light to do with you cat. Also seemed to knock off my service light for a few days although now it has come back on. I was not expecting this to be a permanent fix by any means. Still a great product does what it says on the tin.
G**H
This product works! I saw positive results almost instantly. Good valve for money. I strongly recommend this.
M**7
I've used this product for years. It is a gamble as to whether it may, or may not work. But if it does, then you've saved a bit of money as it is a fraction of the cost of replacing a catalytic converter. If your car is 15, 20, or more years old and you're getting a check engine light with a code for the cat, It's probably not going to work. But if the vehicle is newer than that then there's a very good chance it will work. Also, you want to use the product within a few days of when the check engine light appears and you have confirmed a catalytic converter code. If you wait months after a check engine code appears before adding the cleaner then there is a reduced chance of it working. I typically add a can with less than a quarter of a tank, drive about 50 or 60 miles, fill the tank up with gas from Costco (Costco has a detergent additive in their fuel or use another brand of gasoline with a detergent additive) and add a second can to the newly filled tank.
F**R
Used 2 times in a row, following directions. Even though CEL only came on within 20 days, did not do anything for the problem. Does not work.
M**W
Cheaper than new car
R**N
This product really works! My check engine light was on for a couple months reading that it was the catalic converter. After 2 cans of this stuff, my check engine light has been off for months and haven't come back on.
Trustpilot
2 weeks ago
4 days ago