Received the P0420 code and Honda said I needed a new catalytic converter which $2,609.29 + tax (New Jersey). Being that my '09 Fit Sport has about 160K miles on it, the last thing I really want to do is to spend that kind of money. As I was looking at alternative options, I came across a tip of trying to put a little bit of lacquer thinner in your gas tank and driving 100 or so miles at high to run it through the catalytic converter. Doing so would burn the impurities out of the converter and get rid of the pesky P0420 code.

Anybody have experience with this?

Thank you all for sharing your wisdom.

Mike

 

 

Thanks for the reply. Did he try anything else prior to that?

Also, does anyone know if it could be a faulty O2 censor that's throwing the code?

 

Just out of curiosity,,,how long was "eventually"? Are we talking days, weeks, months or longer?

 

Lacquer thinner sounds pretty sketchy to me. How much added to a full tank of gas? A quart? A few ounces? Maybe they just temporarily "cleaned" the O2 sensor and not the CC. More likely that the lacquer thinner would gum up something in your car (including the O2 sensor) if you use too much. If lacquer thinner was so great for your car, someone would already be selling it at your auto parts store under a different name. At any rate, you should be able to buy a non-Honda CC online for $225 - $300. O2 sensors are even cheaper (and easier to replace). Just make sure that it's a "direct fit" with all the proper dimensions, flanges, etc. "Universal fit" parts are cheaper, but you may need to do some cutting or welding to get a good installation.

In addition to getting a proper diagnosis before spending your money, you might try resetting the OBD codes and see how long it takes for the error message to return. Could be just a fluke.

 

~$250 buys a brand new Walker brand from Rock Auto. Walker is a good brand and Rock Auto ships fast.

I'd just spend the money, bolt it on, and be done. It's easy work and he'd save a lot of potential problems. If that lacquer thinner destroys the primary O2 sensor, he'll be out more money.

 

If you do, document everything- and be sure you have a spare car incase you wreck the fuel system, or somehow prevent proper lubrication of engine internals. I wouldn't pour that shit into my gas tank. Sure it's petroleum based, but you're probably better off diagnosing the O2 sensors, and cleaning/replacing the catalytic converter.

 

They do sell it, not advertised as lacquer thinner but as oxygen sensor or catalytic converter cleaner.

That was the first thing he tried. It was just to get it through inspection. The cat has since been replaced. Yes an oxygen sensor could throw the code and if you replace it get an OEM one.

I would have to ask him. I just know he tried it and when I talk to him again in a month or so it had come back. I would think that if the catalyst is truly damaged or worn it will not fix it.
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