Car P0420 Code Hack

[Jeff]

So I have this 1998 Saturn that runs great with almost 200k, Gets like 30 MPG and everything works on it but I got the dreaded P4020 code which can be many things but on older vehicles it usually means the catalytic converter is not working properly. There is no emissions here on a car this old so I didn't have to fix it but wanted to. So I did a YouTube hack from many people and it actually worked. 1 gallon of lacquer thinner to about a half tank of gas and drive it about 100+ miles at highway speeds preferable above 2500 rpms . Do it at your own risk but the car acted or ran no differently with the thinner in it and I have over 200 miles on it since doing it and the code is gone and the computer has cycled

 

[LS2Silver]

I ran the lacquer thinner and it lasted for about two months. Then I used Cataclean from Walmart and it hasn't come back since. I usually pour it in every six months or so.

 

[Jeff]

I ran the lacquer thinner and it lasted for about two months. Then I used Cataclean from Walmart and it hasn't come back since. I usually pour it in every six months or so.

will try that if it comes back

 

[Jeff]

when the honeycomb in the cat gets dirty it is usually the result of oil or coolant burning in the exhaust . Mine does use a little oil but doesn't smoke.

 

[SMOKESTACK]

Wait !
I quit smoking when I was 17 !

 

[victor93]

Wait !
I quit smoking when I was 17 !

My uncle still smokes keilbasa

 

[Stimpy]

when the honeycomb in the cat gets dirty it is usually the result of oil or coolant burning in the exhaust . Mine does use a little oil but doesn't smoke.

Take the exhaust apart and knock out the cat. it'll sound good too.

 

[Hookman]

420 hack in Ca. means something entirely different.

 

[seabreeze]

So I have this 1998 Saturn that runs great with almost 200k, Gets like 30 MPG and everything works on it but I got the dreaded P4020 code which can be many things but on older vehicles it usually means the catalytic converter is not working properly. There is no emissions here on a car this old so I didn't have to fix it but wanted to. So I did a YouTube hack from many people and it actually worked. 1 gallon of lacquer thinner to about a half tank of gas and drive it about 100+ miles at highway speeds preferable above 2500 rpms . Do it at your own risk but the car acted or ran no differently with the thinner in it and I have over 200 miles on it since doing it and the code is gone and the computer has cycled

Big mistake posting this.
Slave will be trying to sell you a converter.

 

[DCM_Doc]

So I have this 1998 Saturn that runs great with almost 200k, Gets like 30 MPG and everything works on it but I got the dreaded P4020 code which can be many things but on older vehicles it usually means the catalytic converter is not working properly. There is no emissions here on a car this old so I didn't have to fix it but wanted to. So I did a YouTube hack from many people and it actually worked. 1 gallon of lacquer thinner to about a half tank of gas and drive it about 100+ miles at highway speeds preferable above 2500 rpms . Do it at your own risk but the car acted or ran no differently with the thinner in it and I have over 200 miles on it since doing it and the code is gone and the computer has cycled

As you know there are several possibilites for causes for this code. One is oxygen sensor wiring which you probably eliminated since the code is no longer active. It is possible one of the oxygen sensors may have been dirty & the homebrew mixture cleaned it at least temporarly. This state also does not enforce strictly maintaining emission equipment. Most emission equipment is under warranty usually longer than the vehicle drivetrain warranty, but no doubt your Saturn is well beyond that.

 

[slavenomore]

If you're going to get rid of the catalytic converter do NOT use the chain looking handtool sold at harbor freight.
That will just tire you out and it does nothing on that area.

Use a grinder or sawzall. With good carbide blade.

And don't throw it away...when I was having a saga with mine....it got me $100 short of what I paid for the car a few years earlier.
You can sell it online or to a place nearby your house if they buy them.