Has anyone record their factory setting AFR. For example factory computer with o2 sensor. Just want a benchmark.
I just want to know because without the o2, my AEM wideband reads between 16.5-17, mostly around 17, cruising on the highway and light throttle. air pump not in use. WOT around 13.5 and richen as rpm rises.
Car: FC S4 N/A
Mods: Corksport header to vibrant presilencer to borla catback. intake stock. I have safc2 but did not do any correction under light throttle.

 

yep! i've done it on the S4 na, S5 na, and i'm working up an FD

due to the airpump, injecting before the 02 sensor, the idle and cruise will read very lean. without the airpump, it should still be ~14.7:1 between 1100-3500rpm at part throttle

 

I have air pump but its not doing anything, it not injecting air into the exhaust.

 

the stock implementation has the air pump air injecting into the exhaust ports, at idle and low load. Mazda calls it "port air".

since this is in front of the o2 sensor, the o2 reads lean.

 

Is the path from air pump to acv to the exhaust?

 

If you unplug the switching solenoid, this will disable the ACV as it no longer gets air supply from the pump. This will allow you to verify your low load and idle afr.

 

the Air Control Valve, as you might know, controls where the air pump air goes. simply, under 25% throttle, and ~3000rpm, the air pump air goes to the engines exhaust ports. over 25% throttle and about ~3000rpm, the air pump air isn't needed and just gets vented to atmosphere. during transitions, and some cruise situations, the air pump air is sent down the pipe to the catalyst.

if you wanted to know more, the training manual has the specific graphs Foxed.ca - Mazda RX-7 Manuals

 

I had the relieve solenoid unplug, blue connector, the air pump air should vent only, don't have the line that goes to the cat. When I had the stock exhaust manifold and air pump working, wideband read max lean, off the scale. Unplug the blue connector, Afr show richer. I also tried with the hose off from air pump to acv. Same result.

 

Thats normal... I think until you give us more info.

What was your AFR when you disconnected the blue plug?

If you disable the the relief solenoid by unplugging it, your AFR at idle should be stoic if not really close to stoic.

You say "same result" and that is what confuses me.

If you unplug the relief solenoid it effectively makes the ACV completely non-functional and the wide band should indicate what the actual AFR is.

 

i put the wideband on a completely stock FC, and the S4 ran the following:

idle was ~14-16:1, cruise was also in that range, in normal driving the portion where it was in closed loop was pretty small, and so it was usually running at light throttle and port air. it was interesting, if you made big throttle movements, it would pop out of closed loop, and then it seemed like there was a timer to put it back in.

full throttle, it was about 14:1@2000rpm, 12.2@4000rpm, and then it would lean out a tad to about 12.8 right around 5500, and then it got richer after that.

again mine was totally stock, and i didn't check to see if the AFM was completely open like this or not. i have checked other Rx7's and the AFM is usually 100% open before redline, with mods, which means the ecu can't see more airflow

 

It is a timer, the ecu goes into map mode for a second under any throttle change, then goes to the normal flip flopping mode. You'd see it if you had a wide band and a narrow band at the same time. If you stomp on it, it takes longer before it goes back to flip flop mode.

Honestly, I think any S5 car will run better if the switching solenoid is disconnected. The reason I believe this is because the check valves in the ACV (unless you bought a new one your rich person) are shot and allow exhaust gas back into the intake.

Yes the computer will bitch when you are at idle and set off the check engine light, but it goes off as soon as you drive.

 

The Afr I stated in the first post is what I got with the relief solenoid unplug