OK well I have a zt-2 wide band to moniter air fuel. Well I had this problem for like a week streight where the car would go to like 10.1-11.5 under WOT. And some times it would idel at 11.1. Ok so I checked the codes and got the Iat code Intake air temp code. So I changed that and it went away like a day later. Now its doing it again and its throwing a differant code. Now its throwing the Front O2 code. So I changed it and its still throw the code and still runs rich as hell. But some times It will idel at 14.7 and try to crusie at 14.0, But other times it goes rich like 10.5 or so under WOt and idel. I can tell its running rich by gas mileage and performance and the plugs yeild it also.
What could i try to do about this problem?

 

Do you know if the other 02's are good? If they are sending bad readings or you have an exhaust leak they'll run you rich.

 

check my other thread in 4 th gen forum about MAF sensor ground,
faulty ground to MAF will result in stalling and running rich ( carbon fouled sparkplugs)

Nick.

 

ok the o2 should be good Its was brand new but I have not tested it!

Nick shouldn't that set a maf code though

 

mine didn't throw any codes, but the car was stalling and running rich

check this thread http://forums.maxima.org/showthread.php?t=502009

 

I reground the maf anyhow but turn out it was the front o2 Nocode but I change it and its runs fins nice 14.7-14.9 thanks guys

 

yay! im glad you got this fixed because I just purchased a vafc2 and im looking at getting an lc 1 and I didnt want to run into not being able to fix my problem of running rich after spending lots of money to tune with. I have had the problem ever since I did the de-k swap and full 2.5in exhaust. what are you using with the zt-2? the zt-2 only shows you what you are running a/f wise right? you still have to have something to adjust it with right?

 

o2 sensors have no 'say so' whenever in WOT operation.