1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

A/F Meter problem

Thread Tools
 
Search this Thread
 
Old 05-01-05, 01:08 AM
  #1  
Rotary Enthusiast

Thread Starter
iTrader: (14)
 
Slammed_GSL's Avatar
 
Join Date: May 2004
Location: Drifting a Roundabout near you!
Posts: 1,366
Likes: 0
Received 10 Likes on 10 Posts
Unhappy A/F Meter problem

I am installing a Air/Fuel Meter in my 82' 12a carb, welded the bung on and went to test the meter, It show a single led on the rich side, and does not move at any RPM, I did let it get nice and warm but with no change. It is the Autometer brand SportComp 2' 1/16. I went down and purchased another sensor and it did the same thing. The sensor is a single wire model.

Any ideas??????
Old 05-01-05, 02:17 AM
  #2  
Cuisinart on Steroids

 
shadowlife25's Avatar
 
Join Date: Aug 2004
Location: Napa, CA.
Posts: 124
Likes: 0
Received 0 Likes on 0 Posts
The issue you are having is no signal from the O2 sensor to the guage. What exactly did you have to weld? These guages are meant to just tap in to existing factory wiring. IIRC there should be 3 wires that come from your guage : 1 red, 1 black, 1 purple. red goes to switched ignition source, black goes to ground(use a GOOD ground!) and purple taps in to the factory O2 sensor wire. Check to be sure you have positive connections at any splice points, use Only the same guage wire as what comes out of your meter. This is important because you want a clean clear signal that will not provide excess resistance in the current flow to both your guage signal and the ECU signal. Lastly, the meter should read rich while the car is warming up, then it should cycle between lean and stoichiometric at idle. After depressing the accelerator it should go from rich to lean and back to stoich. Usually it takes about 7 minutes for the O2 to really reach temp. This includes warm-up time. HTH
Old 05-01-05, 02:52 AM
  #3  
Full Member

 
RoyFifo's Avatar
 
Join Date: Mar 2002
Location: Kirkland, Wa
Posts: 90
Likes: 0
Received 0 Likes on 0 Posts
while its not probabale that the guage is bad, You can test the sender directly with a digital volt meter.
Old 05-01-05, 07:16 AM
  #4  
What?

 
John64's Avatar
 
Join Date: Sep 2003
Location: CT
Posts: 3,833
Likes: 0
Received 1 Like on 1 Post
Did you solder the connection or crimp it? Do not crip as steted before you need a good connection.
Old 05-01-05, 07:45 AM
  #5  
Savanna Rx-7

 
kenn_chan's Avatar
 
Join Date: Jun 2004
Location: yokosuka japan
Posts: 1,577
Received 12 Likes on 7 Posts
put a grounding strap on your exhasut somewhere, it sound slike a bad ground. You would think that you would get a good ground through the block but a lot of times it doesn't work that way. Gaskets sealers, locktite, anti seize on threads these all conspire to not give a ground for the 02 sensor.

kenn
Old 05-01-05, 09:03 AM
  #6  
What?

 
John64's Avatar
 
Join Date: Sep 2003
Location: CT
Posts: 3,833
Likes: 0
Received 1 Like on 1 Post
Kenn, never thought of that. Its a good idea!
Old 05-01-05, 01:27 PM
  #7  
Rotary Enthusiast

Thread Starter
iTrader: (14)
 
Slammed_GSL's Avatar
 
Join Date: May 2004
Location: Drifting a Roundabout near you!
Posts: 1,366
Likes: 0
Received 10 Likes on 10 Posts
The grounding of the exhaust is sounding like the best place to start. this is a 82' with a carb, no ECU. I will also make sure to solder the connector and not crimp it.

Thanks for the great input!!!
Old 05-01-05, 09:23 PM
  #8  
Rotary Enthusiast

Thread Starter
iTrader: (14)
 
Slammed_GSL's Avatar
 
Join Date: May 2004
Location: Drifting a Roundabout near you!
Posts: 1,366
Likes: 0
Received 10 Likes on 10 Posts
Well I had enough time to ground the exhaust at the section with the bung and still no change. I will check the other connections tommorrow......I'm at work now.
Old 05-02-05, 01:28 AM
  #9  
Rotary Enthusiast

 
jayroc's Avatar
 
Join Date: Jun 2002
Location: Yokosuka
Posts: 1,058
Likes: 0
Received 0 Likes on 0 Posts
Maybe it's just running too rich?
What O2 are you using? If you're using a heated element one make sure you're tapping the right wire. Could be bad sensor?
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
localized
New Member RX-7 Technical
3
09-16-15 12:18 AM
t-von
3rd Generation Specific (1993-2002)
9
09-10-15 01:56 PM
Blk 93
3rd Generation Specific (1993-2002)
11
09-09-15 10:56 AM



Quick Reply: A/F Meter problem



All times are GMT -5. The time now is 09:06 AM.