New headers! Confused - What are these holes?!?!

[Quise]

So I just bought these headers (ts-he-n240sx91-c) and it has 3 holes, one for the 02-censor, one for EGR and i can't find out what the last hole is, it's the biggest one, furthest down from the top. I've been to lowes, mclendon's, and some other shops and i can't find anything to plug this last hole. can anyone help please!!!

okay update, I found out that the bottom hole is for AIV? anybody know the size so i can find something to plug it?

[centralcoaster33]

Well, I looked at the photo on the website for that header. I don't see the third hole in the picture. Did you get it used?

I'm wondering if it would be for a secondary O2 sensor. The one that would normally be after the pre-cat which this header appears to delete. Does your car have 2 (a primary and secondary) O2 sensors? If so, don't plug it, use it with the sensor and possibly a sensor extension to move it out of the exhaust gas flow a bit.

Welcome to NICO Club!

[Quise]

My car has one o2 censor, and i have the censor plugged into the correct spot, I also did an EGR delete. Got the blockoff plate on and I plugged the EGR hole on the headers. I also finally found a plug for the lowest hole and i got it plugged up. The only thing now is i'm having idling issues, It's idling high at bout 2,000 when usually it's at about 1,000. and then it'll take a dip to about 6-700 and sounds like it's going to die. I posted a new thread about that specific issue if you wanna take a look at it. But otherwise I found solutions to all my open holes which was my original problem lol. thank you!