Hey, i'm throwing the p0420 (cat efficiency) code after my tune and zzp dp. I cleared it and it came back like 2 days later. talked with my tuner and he says two things: 1. the obvious - it's gonna keep coming back. and 2. - if you delete the code it MIGHT mess you up for emissions. Anyone have experience with this? I know the dealership does more than check for a cat, they actually plug it up and check the ECM so if I have him clear out the secondary o2 sensor, will this screw me for emissions

The other alternative I was looking at was the spacers i've seen on here for the o2 sensors (supposed to make the sensor sit outside the main flow therefore keeping the numbers in the right range) anyone try them? anyone have them work?

thanks!

 

worth a try, been told that might work or might not. If you wanna save yourself some money, go to your local parts store and buy a pack of 18mm spark plug non foulers, you get 2 of them per pack usually. Run about $5. Only thing is that you have to make the hole bigger to accomodate the o2

 

awesome idea. I may be trying this asap. thank god I JUST got the car inspected literally a few days before the CEL came on. Anyone know about the emissions question in case it doesn't work?

 

find a local shop where the guy will inspect you no questions asked, if you were closer to pittsburgh i know quite a few around here

 

Ya making the hole bigger is no big deal. The nonfoulers are real easy to drill out ,just make sure that the hole is strait and that you dont go all the way through. I have one on my car and it works great.

 

i'll have to look around but there aren't many places in my area to go besides dealers and the odd mom and pop garage who wont do that

a. the hole is straight - I found a how-to on an evo forum and the ones they used looks like the metal is MAYBE 1/16" thick... is this the hole you're talking about? or a different one i'm not seeing?

a. go all the way through... what?

here is what I'm looking at

bump for some more info!

 

i drilled mine all the way through... didnt seem to affect anything. Ya, thats what mine look like after being drilled. If you have access to a lathe, I would recomend using it, that way you know for certain that the hole will be drilled striaght... Oh, just as a side note, i was a lazy bastard and put off installing my spacers. I had my stage 2 installed (dealer) and ever since I got it back from the shop, CEL hasnt come on since. So if spacers dont work. buy a stage 2 kit! LOL...

 

ok so I got the non foulers and drilled one of them out and went to install it and there is not enough room. anyone who did this have this problem? and what did you do about it?