Test pipes/high-flow cats users please advise on this.

Long story short. I installed high-flow cats and did the "CEL fix" by installing the spark plug de-foulers over the secondary sensors (1 de-fouler for each sensor) and did the hard reset by disconnecting the negative battery terminal.

The light went off but after driving 50 miles or so, the SES light came back on.. Any ideas on how to have this solved?

Note: i'm hearing a low hissing sound, does the SES light goes on if there's an air leak, or in other words, what causes an SES light to show.

Thanks.

One sure way to fix the SES is to find out what the error code is and means. Could be one of the sensors behind the test pipes, that's most common....but ya gotta find out.
Gary

Thanks Gary. I didn't know there were multiple codes for the exhaust system itself, i'm gonna have it scanned and see which code shows up.

That hissing sound is probably just the air flowing through the piping now that the exhaust isn't as restricted. I had that noise too when I had HFC's installed.

I guess Nissan designed the entire exhaust based on having two catalytic converters.. One little mod & you get all sort of noises. I'm facing a hissing sound and rasp. The overall "G35 sound" however, has become louder and deeper.. which is VERY fine by me.

I have HFC's and no SES. Usually test pipes will throw it though.

Hfc's and no codes here

I have Kinetix HFC and have yet to see an ses light. No defoulers installed just 02 right into the bung.

As for exhaust codes there are quite a few codes that could come up. Just have to get it scanned and see what it actually is.

I had it reset 2 nights ago so now the light is off. Once it pops out again (pray to God it won't), but just in case it does, i will have it scanned and will post the code and see how it goes.

Thanks fellas

I have hfc and my light is on.. I tried put spark de foulers and it was too long i.couldnt twist in

I see you got Berks HFC like i do. I did manage to have the de-foulers bolted on though.

^ ya attaching the foulers on to sensor made it longer and theres no way im able to bolt on it keeps hittin... And I gotta get car inspected next month which sucks

The 05-07's usually throw codes even with non foulers.

Also Megan Racing makes a 90 degree angled non fouler so your secondary o2's won't hit the trans.

i had some generic hfc's and i had the check engine light after the cel fix. I also had a hissing sound too. turns out i cracked my cat when i went over a huge bump. i replaced the hfc's with kinex hfc's and no hissing and no cel. Check for leaks. I used oem gaskets as well. the chinese ones leak.

Does anyone technically know why the Kinetix HFC do not throw the CEL, and no CEL fix is required neither..