I have a '99 Protege LX Touring edition with a 1.8L engine.

It just recently failed the emissions test and I'm trying to figure out why and how to fix it. The check engine light is on and it is giving three seperate codes; P0420, P0463, and P0455.

The emission test is the ASM2525 Test and the car failed on the "CO%" and the "NO ppm", but not by a lot.

Any help you can give to diagnose why it failed and how to fix it so it can pass would be greatly appreciated.

Thanks

 

i don't know the codes, but i would guess that since you are pulling 3 and failed emissions, it has something to do with the o2 sensors. go to autozone or a mechanic and get them to pull the meanings of the codes.

 

I had the same code happen on my car and also failed emissions. It's your EBR boost sensor. Here is an article I found on how to fix the problem...
http://www.asashop.org/autoinc/sept2002/techtips.htm