A/F ratio meter not displaying rich-help
08-29-2001 | 06:12 PM
#1
Thread Starter
Member
Joined: Jun 2001
Posts: 38
Likes: 0
A/F ratio meter not displaying rich-help
Hi guys,
Just DIY install the Autometer A/F Ratio Meter and am curious to know is it normal to have the max "richness" of only one green bar?
most of the time its bouncing between nothing till just before the 1st green (0.750mV)
if its not normal, how can i "adjust" it?
wonder if the cable used is part of the factor..(from purple wire of meter linked to a single strain wire)
thanks in advance,
sockman
Just DIY install the Autometer A/F Ratio Meter and am curious to know is it normal to have the max "richness" of only one green bar?
most of the time its bouncing between nothing till just before the 1st green (0.750mV)
if its not normal, how can i "adjust" it?
wonder if the cable used is part of the factor..(from purple wire of meter linked to a single strain wire)
thanks in advance,
sockman
08-30-2001 | 07:32 AM
#2
Super Moderator
Joined: May 2001
Posts: 11,851
Likes: 2
From: Rancho Palos Verdes, CA
Vehicle: 2008 Toyota Prius 2006 Suzuki SV650S
Well, from my recent experience messing with my 02 sensor and readings..
0.000 is Lean, 1.000 is Rich 0.500 is perfect.
It is normal for it to "bounce" at idle like that. Mine varies between 0.2 and .7 at idle.
To get an over rich condition (beyond .75V) to test your gauge, a quick full throttle run in 5th gear should do it. At full throttle the ECU should stop listening to the o2 sensor and dump fuel. That should cause you to go up above .750
Don't rely on that A/F gauge for too much though, and not for tuning, just for general information.
0.000 is Lean, 1.000 is Rich 0.500 is perfect.
It is normal for it to "bounce" at idle like that. Mine varies between 0.2 and .7 at idle.
To get an over rich condition (beyond .75V) to test your gauge, a quick full throttle run in 5th gear should do it. At full throttle the ECU should stop listening to the o2 sensor and dump fuel. That should cause you to go up above .750
Don't rely on that A/F gauge for too much though, and not for tuning, just for general information.
08-30-2001 | 10:34 PM
#3
Senior Member
Joined: Jul 2001
Posts: 749
Likes: 0
I find it interesting that we can't use our O2 sensor to tune the car, but that's what our ECU relies on to tweak the fuel maps (among other things).
I agree with Random and others who say you can't tune with it, the curve is too steep. The voltage stays high, then drops like a mountain, then flattens out (sorta like this -_). It changes so much in that center region that fine tuning is impossible. That, and the reading vary with exhaust temperature, so it could throw a lean reading when the mixture was rich after a long, hot run.
Anyway, it just seems interesting that our ECU relies on it and we can't.
The only kind you can tune with are wideband O2's, and they are expensive ($150 to $200). I don't know if they put out the same voltage range or not.
a
I agree with Random and others who say you can't tune with it, the curve is too steep. The voltage stays high, then drops like a mountain, then flattens out (sorta like this -_). It changes so much in that center region that fine tuning is impossible. That, and the reading vary with exhaust temperature, so it could throw a lean reading when the mixture was rich after a long, hot run.
Anyway, it just seems interesting that our ECU relies on it and we can't.
The only kind you can tune with are wideband O2's, and they are expensive ($150 to $200). I don't know if they put out the same voltage range or not.
a
08-31-2001 | 03:13 AM
#4
Super Moderator
Joined: May 2001
Posts: 11,851
Likes: 2
From: Rancho Palos Verdes, CA
Vehicle: 2008 Toyota Prius 2006 Suzuki SV650S
Where can you get a wideband O2 for $200? All the units I have found are $1000 or higher!
The reason you cannot "tune" with them is that they are only good for a very narrow range, which is all the stock ECU can control. The Stock ECU/o2 sensor only has controls over 10% of fuel delivery (up or down 10%).
So the ECU can do it's job with just some fine tuning on a fairly stock car, but the more mods you throw at the stock ECU and 02 sensor...the more you increase the chance of running lean/rich beyond the control of the stock ECU (hence the S-AFC, Uni-Chip or other ECU "piggybacks").
The reason you cannot "tune" with them is that they are only good for a very narrow range, which is all the stock ECU can control. The Stock ECU/o2 sensor only has controls over 10% of fuel delivery (up or down 10%).
So the ECU can do it's job with just some fine tuning on a fairly stock car, but the more mods you throw at the stock ECU and 02 sensor...the more you increase the chance of running lean/rich beyond the control of the stock ECU (hence the S-AFC, Uni-Chip or other ECU "piggybacks").
09-02-2001 | 11:28 AM
#5
Thread Starter
Member
Joined: Jun 2001
Posts: 38
Likes: 0
Thanks Random, will be trying the quick full throttle at 5th. Just want to make sure that the meter is working correctly.
mine actually "bounce" from 0 to 0.7 at idle..
when you are cruising, it is bouncing much faster...this means that it is in open loop and using the ECU mapping right?
my plan is to find all the "rough" points that i want to adjust when i get the SAFC.
sockman
mine actually "bounce" from 0 to 0.7 at idle..
when you are cruising, it is bouncing much faster...this means that it is in open loop and using the ECU mapping right?
my plan is to find all the "rough" points that i want to adjust when i get the SAFC.
sockman
09-02-2001 | 12:08 PM
#6
Super Moderator
Joined: May 2001
Posts: 11,851
Likes: 2
From: Rancho Palos Verdes, CA
Vehicle: 2008 Toyota Prius 2006 Suzuki SV650S
Sockman-
If I may suggest. Invest another $200 in dyno tuning the SAFC. You will get better gains, and more reliable results.
Trying to tune with the stock 02 sensor is like trying to drive with pinhole glasses on. The 'window' that stock o2 sensors report on is very small...
If I may suggest. Invest another $200 in dyno tuning the SAFC. You will get better gains, and more reliable results.
Trying to tune with the stock 02 sensor is like trying to drive with pinhole glasses on. The 'window' that stock o2 sensors report on is very small...
09-02-2001 | 02:06 PM
#8
Super Moderator
Joined: May 2001
Posts: 11,851
Likes: 2
From: Rancho Palos Verdes, CA
Vehicle: 2008 Toyota Prius 2006 Suzuki SV650S
Ah..forgot you were in Singapore.
the ITC should really only be needed if you are running forced induction...in which case, A Haltec EK6 would serve 100 Times better than a SAFC/ITC combo, for only a little more money.
the ITC should really only be needed if you are running forced induction...in which case, A Haltec EK6 would serve 100 Times better than a SAFC/ITC combo, for only a little more money.
09-03-2001 | 10:05 AM
#9
Thread Starter
Member
Joined: Jun 2001
Posts: 38
Likes: 0
tried the quick throttle at 5th...the max it display is one green led...hmmm...
will be checking the voltage output soon...if it is less than 0.75 v - i'm alrite...
this is strange cos another Accent display the full range(which i think is norm)
maybe is the wire conductivity...hmmm
the worst thing is...the ain't many competent tuner in s'pore(would even bother if they see an Accent)
will be checking the voltage output soon...if it is less than 0.75 v - i'm alrite...
this is strange cos another Accent display the full range(which i think is norm)
maybe is the wire conductivity...hmmm
the worst thing is...the ain't many competent tuner in s'pore(would even bother if they see an Accent)
09-03-2001 | 11:20 AM
#10
Senior Member
Joined: Jul 2001
Posts: 749
Likes: 0
Random,
I got $200 from the Greddy unit price: $300. It comes with the gauge and supposedly a wideband O2. I figured $200 for the replacement sensor and $100 for the gauge and pod. Now whether it is a true wideband, or pseudo-wideband, I dont' know. I'm still waiting to hear from them.
a
I got $200 from the Greddy unit price: $300. It comes with the gauge and supposedly a wideband O2. I figured $200 for the replacement sensor and $100 for the gauge and pod. Now whether it is a true wideband, or pseudo-wideband, I dont' know. I'm still waiting to hear from them.
a