Yep, I've got them p0420, p0430 codes triggering my CEL, too. I came across this idea promoted by Scotty Kilmer in a Youtube video. He recommends putting a gallon of laquer thinner in a half-full gas tank, then running the engine for "150 miles or so at higher speeds".
Now, I've been trying to research this since I'm no chemist. It seems many people are trying it and having success. However, I'm also reading many others are wary of putting it in their car at all.
Considering the alternatives, this is very attractive as it sounds like a great idea and a potentially easy fix. But is there any reason at all to worry about putting this stuff in my fuel system? Can it harm the fuel pump, fuel lines, o-rings, gaskets, or anything it's going to come into contact with on its way to the cats?
I saw that video too. Some of his fixes or rigs are crazy. I think he also suggested washing the cat in a bucket with soapy water. I would try it just for fun if any of my cars were throwing catalyst efficiency codes (the thinner, that is.)
RIP '94 Amber Fire Pearl Metallic Thunderbird on Bullitts [email protected]
96 Sport '02 Explorer PI with ported heads, 90MM LMAF, DirtyDog Marauder TC, Lasota tune, Jmod, Magnaflow mid-mount with X, no cats. Urethane drivers motor mount. HIDs!
I would never reuse cats if they ever got dirty enough to clean unless I keep up on that myself from new.
If they're clogged, replace them. Period.
But before you do that get the motor running right. Fix the cause, not the effect.
Mods? Yea, I got mods ... Air silencer delete, warp drive, dilithium crystals, flux capacitor, Slingshot Rubber band power adder, Moonshine & Gas, Leaf Blower Supercharger, Hamster Wheel & Hamster, Energizer Bunny generating 1.21 gigawatts, Mr. Fusion® Home Energy Reactor, hover conversion and a sextant celestial navigation system (The original GPS)
Best 1/4: 1,320 nanoseconds @ 670,616,629.2 miles per hour
"There isn't that much difference anymore between spacecraft, aircraft and modern automobiles..." - Keith Henry, NASA's Langley Research Center
See a list of my real mods and pictures of my car HERE. The true performance of my car was made possible by the Carolinas Crew Chief, RobertP at Rob's Tire & Auto