Stock AFRs with AEM wideband?

[JMiller]

I just installed my AEM EUGO Wideband last night and was wonder what AFRs are normal for a mostly stock setup. I put the sensor in the rear O2 spot(catless exhaust). When the car is off it reads around 14.7, when i start it it goes 12.3 and idles at 12.3, WOT is 10.1-10.7, Full deccel leans completely out --:1, cruising is about 13.4-13.8. As soon as it sees boost it goes 10.5-11.2, If i ease into boost slowly it will lean out some 13.2 then start to add fuel until im back in the 10.--. Are these numbers normal or is it to rich i only run 1.0bar(14.7psi). Thanks to anyone that responds.

 

[GRAVEDIGGER]

Sounds about normal to me. They are set up to go pig rich under boost for a little added safety cushion for the motor.

 

[JayRolla]

Sounds good also. Thats actually a little lean for stock. If it hits 11.1 at WOT thats about perfect on pump gas. I would target 11.1 at WOT and 14.7 at idle and light cruise.

 

[JMiller]

Cool, thanks. It's my first wideband and I just wanted to make sure it was reading correctly before I dynoed it today. It read 11 throughout every pull at 14psi and tapped 12:1 when I spiked 18psi when I had it set to 16psi. Afterwards I drove 2 hours all highway and stayed around 12:1 during cruise and 11:1 on accel. I will post my dyno results in my profile soon.

 

[staztrx250]

I just installed my AEM EUGO Wideband last night and was wonder what AFRs are normal for a mostly stock setup. I put the sensor in the rear O2 spot(catless exhaust). When the car is off it reads around 14.7, when i start it it goes 12.3 and idles at 12.3, WOT is 10.1-10.7, Full deccel leans completely out --:1, cruising is about 13.4-13.8. As soon as it sees boost it goes 10.5-11.2, If i ease into boost slowly it will lean out some 13.2 then start to add fuel until im back in the 10.--. Are these numbers normal or is it to rich i only run 1.0bar(14.7psi). Thanks to anyone that responds.

something doesn't sound right here. i would check you calibrations because no matter what if your stock it should read 14.7 at idle and cruse. at those points it should the ecu is in closed loop and it should be correcting your afs. This could also be a sign of a bad front o2 sensor.


everything else sounds normal that 13.2 reading you got is normal it happens because you're not under that much load less load= closer to 14.7 afr. more load= richer


edit: you didn't remove you're front o2 did you? because you can't just do that. Your ecu needs that for closed loop

 

[JMiller]

I didn't remove my front O2, but i have been thinking it was bad for awhile now. Once my car has warmed up and been driven for about 5-10 min i can get about 13:1 cruising with about 20"Hg. I also know i have a boost leak that i haven't had time to fix (throttle body shaft seals). Depending on how my week goes i might replace the front O2 sensor, cause when i pulled the rear O2 it had a build up of carbon on it.