2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.
Sponsored by:

A/F Ratio Gauge

Thread Tools
 
Search this Thread
 
Old 10-05-04, 02:52 AM
  #1  
Rotor Head

Thread Starter
 
DC350's Avatar
 
Join Date: Jan 2002
Location: British Columbia
Posts: 1,966
Likes: 0
Received 0 Likes on 0 Posts
A/F Ratio Gauge

Not sure what it is with my a/f gauge but it seems to go ape **** at about over 60% throttle it goes from Rich to lean and back very quickly, i think its still reading just the LEDS dont stay in one spot...

This is hard to explain but i'll give it my best.. They should be in one spot moving from rich to lean or whatever slowly... just the leds go back to LEAN but when moving up the gauge rapidly and repeat so fast, they stop at where the a/f is....


Anyone else have this problem??


But under 60 percent throttle they seem to work properly.. could this be because of untuned 710 cc secondaries?


evan
Old 10-05-04, 04:11 AM
  #2  
Moderator

iTrader: (7)
 
hIGGI's Avatar
 
Join Date: Feb 2001
Location: Czech Republic [www.rx7cz.net]
Posts: 4,985
Received 17 Likes on 12 Posts
Have u tried another O2 sensor?
Old 10-05-04, 07:39 AM
  #3  
spending too much money..

iTrader: (2)
 
hondahater's Avatar
 
Join Date: Dec 2002
Location: louisiana
Posts: 10,117
Likes: 0
Received 1 Like on 1 Post
first off they are not accurate at all and usually when it is oscillating like that it means it's in closed loop.
Old 10-06-04, 11:48 AM
  #4  
1 BAD 7

 
Donn Hecht's Avatar
 
Join Date: Feb 2003
Location: Miami,Fla
Posts: 277
Likes: 0
Received 0 Likes on 0 Posts
I have a Halmeter AF-30 but it's only in there for show.
I really dont trust those A/F Gauges for nothing.
I think your just better off buying a wideband, and a EGT gauge.
Then go to the dyno for some fine tuning.
Old 10-06-04, 12:53 PM
  #5  
Full Member

 
oztofrdm's Avatar
 
Join Date: Aug 2004
Location: nc
Posts: 174
Likes: 0
Received 0 Likes on 0 Posts
what is the difference in a wideband o2 and what is a EGT guage
Old 10-06-04, 01:29 PM
  #6  
Rotary Enthusiast

 
Pinfield357's Avatar
 
Join Date: Sep 2001
Location: Pittsburgh Pa
Posts: 1,417
Likes: 0
Received 0 Likes on 0 Posts
EGT= Exhuast Gas Temperature

also a widband is much more accurate than just the stock set up but your going to be looking at around at least $300 for just the sensor and the stuff to pick up the signal
Old 10-06-04, 01:29 PM
  #7  
Full Member

 
DjRannyKan's Avatar
 
Join Date: Jun 2003
Location: Cuyahoga Falls Oh
Posts: 238
Likes: 0
Received 0 Likes on 0 Posts
exhaust gas temp
Old 10-06-04, 01:50 PM
  #8  
i am legendary

 
ddub's Avatar
 
Join Date: Sep 2003
Location: Kirkland, WA
Posts: 8,478
Likes: 0
Received 0 Likes on 0 Posts
I call my autometer a/f gauge a rainbow gauge cuz the lights flash back and forth so quickly!

Narrowband = crap. Only time it remotely works is on hills or at WOT
Old 10-06-04, 02:02 PM
  #9  
Full Member

 
oztofrdm's Avatar
 
Join Date: Aug 2004
Location: nc
Posts: 174
Likes: 0
Received 0 Likes on 0 Posts
your saying that it would cost me $300 or an o2 sensor. f that. whats soo much better about them
Old 10-06-04, 02:04 PM
  #10  
SUPERnaturally Aspirated

 
shiftnmadkwik's Avatar
 
Join Date: Dec 2003
Location: Long Island
Posts: 337
Received 0 Likes on 0 Posts
yeah when in closed loop the ecu is making changes to the mix and the gauge is too innacurate to make an accurate reading so you get the bounce. those gauges are pretty much good as idiot lights so that you can see if you go full lean WOT.. get a wideband with a 0-1v output and you can turn that guage into a real tuning meter
Old 10-06-04, 02:06 PM
  #11  
Lives on the Forum

 
WAYNE88N/A's Avatar
 
Join Date: Feb 2004
Location: Coldspring TX
Posts: 5,721
Likes: 0
Received 2 Likes on 2 Posts
I don't know where all this flaming against the "normal" O2 sensor comes from (or by extension the "normal" A/F gauge- put your meter on that biatch at the ECU while driving and keep an eye on it for a while...What you will find is damn near instantaneous reactions to varying fuel/air conditions, and a sampling/response rate that exceeds 5 per second. Within a certain range, they are every bit as good as the widebands. My humble opinion for the day

BTW- an accurate oscillation between .4 and .5 volts at cruise tells me that bad boy is pretty damn accurate- could you tell the difference of .1v worth of O2 content if exhaust was shoved up YOUR ***?

Last edited by WAYNE88N/A; 10-06-04 at 02:08 PM.
Old 10-06-04, 02:08 PM
  #12  
Seduced by the DARK SIDE

 
SureShot's Avatar
 
Join Date: Apr 2001
Location: Orange Park FL (near Jax)
Posts: 7,323
Likes: 0
Received 2 Likes on 2 Posts
Mine works the same way.
The bouncing is normal closed loop ECU tuning with the oxygen sensor.
The standard A/F gauge is kind of on/off.
I'm saving for a wideband this month.
http://www.plxdevices.com/index.htm

Check out this video link to see the comparison. click here

Last edited by SureShot; 10-06-04 at 02:11 PM.
Old 10-06-04, 02:30 PM
  #13  
Eat, sleep, work, mod.

 
jon88se's Avatar
 
Join Date: Jun 2001
Location: Long Island
Posts: 2,517
Likes: 0
Received 0 Likes on 0 Posts
I've heard that during a dyno test with a wideband, the GReddy AF gauge (with it's own narrow band sensor) is spot on with the wideband...

For the cheapy light gauges, think of it as an O2 sensor tester
Old 10-06-04, 03:34 PM
  #14  
spending too much money..

iTrader: (2)
 
hondahater's Avatar
 
Join Date: Dec 2002
Location: louisiana
Posts: 10,117
Likes: 0
Received 1 Like on 1 Post
Originally Posted by oztofrdm
your saying that it would cost me $300 or an o2 sensor. f that. whats soo much better about them
Um if you have an n/a pretty much stock then don't worry about getting a wideband o2 sensor however if you have a turbo and lots of mods that could blow your engine up if its starved of fuel then you need to get yourself a wideband to see exactly how lean or rich your car is. Wayne is smarter than me so he probably has some sort of multimeter setup at the ecu and has the geometrical logitudinal graphical interface spliced in with the cpu and test the a/f numbers that way but for us guys that are more neandratholic we like to have a pretty much plug and play device that will show us how lean or rich we are with accuracy! And for this we get widebands http://www.plxdevices.com/index.htm is one that alot of people get because of the simplicity and size.
Old 10-06-04, 03:43 PM
  #15  
Clogged cat

iTrader: (3)
 
koukifc3s's Avatar
 
Join Date: Sep 2002
Location: Orange County, CA
Posts: 2,000
Likes: 0
Received 0 Likes on 0 Posts
Would the M-300 @ $329 work ok?
Old 10-06-04, 03:44 PM
  #16  
Seduced by the DARK SIDE

 
SureShot's Avatar
 
Join Date: Apr 2001
Location: Orange Park FL (near Jax)
Posts: 7,323
Likes: 0
Received 2 Likes on 2 Posts
Originally Posted by oztofrdm
your saying that it would cost me $300 or an o2 sensor. f that. whats soo much better about them
Check out the links in my previous post...
Old 10-06-04, 03:49 PM
  #17  
spending too much money..

iTrader: (2)
 
hondahater's Avatar
 
Join Date: Dec 2002
Location: louisiana
Posts: 10,117
Likes: 0
Received 1 Like on 1 Post
yeah the m300 is the one I'm going to get
Old 10-06-04, 03:55 PM
  #18  
Resident Know-it-All

iTrader: (3)
 
patman's Avatar
 
Join Date: Aug 2002
Location: Richland, WA
Posts: 3,099
Likes: 0
Received 3 Likes on 2 Posts
a 'normal' O2 guage is supposed to do that. that means its in closed loop, and that the ration is hovering right around 14.7. for an NA, this is perfect. For a stock turbo, you should see that off boost, and a rich reading on boost. This type of guage is very accurate within the stoich range, but not much good outside of it. If you have a modified turbo car, you might want to get a real O2 guage, or just have the car tuned right and not worry about it.

pat
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
stickmantijuana
20B Forum
21
03-22-22 01:00 PM
ZacMan
Build Threads
4
09-19-15 09:20 PM
The1Sun
1st Generation Specific (1979-1985)
7
09-18-15 07:13 PM
The1Sun
New Member RX-7 Technical
5
09-15-15 04:45 PM
t-von
3rd Generation Specific (1993-2002)
9
09-10-15 01:56 PM



Quick Reply: A/F Ratio Gauge



All times are GMT -5. The time now is 03:04 PM.