Hello me again. I was curious what type of high performance catalyst converters you guys use and/or resonators.

My check engine light is on for the following engine codes so if anyone knows of these codes or can point me in the direction of where to read up on them thank you.

1. P1259

2. P0420

 

google is your friend
P1259 VTEC System Malfunction
"P0420 Catalyst system efficiency below threshold (bank1)"

 

For one my car doesn't not have Vtec to my knowledge. If anyone knows how to check please let me know.

and


"P0420 Catalyst system efficiency below threshold (bank1)"

That is because my resonator is gone and i gutted my cat converter. Anyone know what could fix this and not the stock cat.

 

what year make model is your car. what enigine does it have

your o2 sensor might be bad i have had civics before with no cat/resonator and no cel lights

 

You can have no catalytic converter and no check engine light on OBD-I cars, but cars with OBD-II you will trip your check engine light. In order to shut the CEL off with no cat, you have to get a mechanical O2 simulator, or get a high-flow cat.

Personally, I see no point in not having a cat on street cars. With a high-flow cat you get about 1 less hp. But it makes your car legal, you don't pollute the environment, and you don't get that sh!tty raspy sound that you get without a cat. Basically, it's not worth it to not have a cat. Even if you keep a stock one on, your only losing a couple hp, and the benefits outweigh the negatives.

But if you must, here's a good link on how to do the Mechanical O2 sensor...
http://www.civicforums.com/forums/79...simulator.html

 

i used to have no resinator niether a cat and it was loud an disgusting now i got a magnaflow cat with a cherry bomb glasspack resinator and its sounds nice

 

also what ECU?
you could have a vtec ecu w/o a vtec motor and it would throw the code.....or you could have a malfunctioning VTEC system

 

1999 civic si sohc 1.6L 165hp (no vtec)

 

ummm what?
i dont think that exists