Why a wide-band oxygen sensor on the RX8??
#1
Registered
Thread Starter
Join Date: Sep 2004
Location: Europe
Posts: 581
Likes: 0
Received 0 Likes
on
0 Posts
Why a wide-band oxygen sensor on the RX8??
I'm really curious to see if anyone has an idea why our RX8 are fitted with a wide-band lambda sensor considering it apparently (=as far as I have observed with my sCANalyser) only runs in close loop at a stoichiometric AFR. Therefore, a switching HEGO would have done the job as well, if not better.
I have one or two ideas, but I'd like to hear your opinion about it too.
Thanks,
Fabrice
I have one or two ideas, but I'd like to hear your opinion about it too.
Thanks,
Fabrice
#2
Registered
Join Date: Aug 2003
Location: Brisbane, Australia
Posts: 1,459
Likes: 0
Received 0 Likes
on
0 Posts
My thoughts:
1. Hardware or software limitations with the PCM
2. Flexibility - maybe Mazda thought there may be some need to do some behaviour based on wideband O2 readings (e.g. looking at cat temp + current AFR to determine dump rate of extra fuel for cooling purposes)
1. Hardware or software limitations with the PCM
2. Flexibility - maybe Mazda thought there may be some need to do some behaviour based on wideband O2 readings (e.g. looking at cat temp + current AFR to determine dump rate of extra fuel for cooling purposes)
#4
Registered
Thread Starter
Join Date: Sep 2004
Location: Europe
Posts: 581
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by sco
My thoughts:
1. Hardware or software limitations with the PCM
2. Flexibility - maybe Mazda thought there may be some need to do some behaviour based on wideband O2 readings (e.g. looking at cat temp + current AFR to determine dump rate of extra fuel for cooling purposes)
1. Hardware or software limitations with the PCM
2. Flexibility - maybe Mazda thought there may be some need to do some behaviour based on wideband O2 readings (e.g. looking at cat temp + current AFR to determine dump rate of extra fuel for cooling purposes)
1- Initial program assumption might have included some relatively lean burn operation or close loop WOT running but it was canceled for XYZ reason during the program but they had to remain with the same hardware and software (PCM) for cost reasons.
2- Diagnostics : it might be used by the OBD system to monitor the engine management, and maybe to better infer the catalyst temperature.
The Mazda RX8 Training course (borrowed from my dealer) does not give any answer either.
I will also ask the question to some Ford engineers I know.
Fabrice
#5
Go Texas Longhorns!
Emissions were such a issue with the previous cars I'm sure it just helps the PCM better manage the emissions profile and keep the car operating in a clean manor.
#6
Registered
Thread Starter
Join Date: Sep 2004
Location: Europe
Posts: 581
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by brillo
Emissions were such a issue with the previous cars I'm sure it just helps the PCM better manage the emissions profile and keep the car operating in a clean manor.
F
#8
Registered
Thread Starter
Join Date: Sep 2004
Location: Europe
Posts: 581
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by MazdaManiac
Because the A/F target is closer to 12.5:1 in closed loop at some load points.
F
#10
Registered
Thread Starter
Join Date: Sep 2004
Location: Europe
Posts: 581
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by MazdaManiac
4800 RPM to 6250 at 10% to 35% absolute load after 10 to 15 seconds at vehicle speeds over 35 MPH.
F
#11
Registered
Thread Starter
Join Date: Sep 2004
Location: Europe
Posts: 581
Likes: 0
Received 0 Likes
on
0 Posts
Mmmh, can't see it on mine. Here are some data :
- RPM : 5500 to 6000 rpm
- Lambda : slightly rich
- Load_abs : between 20 and 25%
- Fuel System Status : OPEN LOOP!
Don't seem to be running in close loop. Will do some specific runs tomorrow.
Fabrice
- RPM : 5500 to 6000 rpm
- Lambda : slightly rich
- Load_abs : between 20 and 25%
- Fuel System Status : OPEN LOOP!
Don't seem to be running in close loop. Will do some specific runs tomorrow.
Fabrice
Thread
Thread Starter
Forum
Replies
Last Post
Pelleilee
New Member Forum
6
09-29-2019 10:07 AM
dweezil22
NE For Sale/Wanted
12
09-09-2015 10:50 AM
akagc
RX-8's For Sale/Wanted
7
08-11-2015 07:07 PM