idle and to lean problems after headers and sim installed??!

[mattaltima99]

I have a 99 altima that i put ebay 4-1 headers on and deleted the cats and o2's. i put a o2 sim on the car that adjusts for the heaters wires and voltage. the car after a couple of miles of driving or so will get the SES light and it will come up on the computer as knock bank 1 to lean..... i have adjusted the s$!t out of the tuner and still havent gotten anywhere. there is also a small leak on cyl 1 on he header flange and the egr doesnt hook up all the way into the headers so it has a little leak. i have welded the egr hookup though on the header so it doesnt leak and i still get the knock bank 1 to lean code!!! the car has a slightly bumpy idle kind of like its loping??? i dont know what else to do!!! Please help thanks!!
Matt

[QR25DE]

Don't drive it. I know this post is old, but you're doing damage. Put the stock header and o2 back on to see if that makes a difference, however, driving with it lean will cause damage.

[mattaltima99]

Thanks for the reply but i solved the issue of the lean problem. There was a cracked egr hose running to its vaccum and not recycling properly. I replaced the hose and its running 14.6 on the meter for a/f:)

[QR25DE]

Nice!