I did the double spark plug non fouler fix and it worked for about 150 miles then came on again.... On my evo at the rear bung on the test pipe there was not enough clearance to put it on there. But the cord for the o2 sensor was long enough so i put it up at the front of the test pipe where the wideband would normally go and stuck that plug in the rear opening of the test pipe. Could that be why its not working? Its plugged in right where the downpipe comes down into the test pipe so there may be more flow there then if it was at the rear bung in the test pipe... any suggestions? responses? Has the spark plug non fouler fix not worked for anyone else? I used both pieces not just the one. Thanks in advance!!!

 

I still get the codes even with antifoulers

 

It worked for me but I have a high flow cat.

 

Spark plug non foulers are definitely hit and miss. They work just fine for 80% of the population but the rest are screwed. It works for me but every once in a while I'll get a CEL for cat inefficiency.

 

are there any other options at all?? besides putting my cat back on that is.... guess not... guess i will be driving around with the CEL for the rest of the cars life.. what if something really came up where the CEL would need to notify me.. i would never know!

 

Some companies also make Cel eliminators might want to try that out .

 

you can turn off the rear o2 sensor (so no more p0420) with a tune, but you'll need to physically remove the sensor so you don't hurt it (they are $$).

 

I have the SC tp with the "built- in" cel fix. Still a light, and it doesn't change adding anti-foulers to it.

 

Well i may try moving the o2 sensor back to the rear bung on my test pipe. Just need to figure out how to make it so it has enough clearance to fit without hitting the underside of my car. Thx for all the comments. I may just be stuck with the CEL for eternity!

 

hey im having an issue like this. i need to get my car inspected and on stock ecu its throwing the p0420 code. the car had hfc from don herring when i bought it. any way to get around this code and pass emissions. their service is quoting me 350bucks for inspection and labor and i wont pay that for a car with 6k miles on it that was guaranteed to not have emissions issues with this setup. anyone know how to check the ready cycle for the sensors, maybe i can sneak in before the code pops up after reset.

 

might want to try a J bung.. Vibrant does sel la screw in type one, wich would make it easy for you to try..
here's pic ,btw you need to install the J so the sensor is agains flow (sees less exhaust)

 

try some steel wool trick or disable the CEL via the ECU or get PCMscan to clear the codes.

 

I have the T1R Elbow style on my car and the CEL didn't come on anymore. I had the straight design and the CEL came on after a couple days.

Dennis

 

i have the ultimate racing mini muffler test pipe....i got the CEL once during a 1000 mile span....if it pops up once every 500-1000 miles....I will be happy with that....it can't be perfect right?

btw i got P0137 as my code, not the typical P0420

 

I have an elbow AND an added spacer. It got rid of the CEL until I'm low on gas, every time my car gets low I throw a code for cat efficiency.