[SAMMYJAMMY]

I have a 87 Sammy with a weber 38 outlaw, I just got a JDM Air/fuel ratio gauge. I install were the clock was, and I use the power and ground from the clock, so it turns on and off with the key, but it seems like the gauge does not read the air ratio until it is warm and no matter how I adjust the carb, it does not effect the gauge the way it should. I spliced into the O2 wire at the engine, but just before the plug on it,that goes into the harness. I think I might need to move were I spliced into the O2 wire, and if so , what is the best spot.

 

[fordem]

The O2 sensor will not respond until it's at operating temperature, and if I'm not mistaken an 87 would have had a one wire O2 sensor, that's dependent on exhaust gas flow to bring it up to temp, so that "not responding until warm" that you describe is what I would expect.

You could try a four wire O2 sensor with the heater powered from an ignition controlled relay, that will come up to temp faster, within 30 seconds or so.

I have a strong suspicion that the a/f gauge will never show you what you think you should be seeing - it's going to show rich most of the time or lean most of the time, with the occasional flicker - they don't quite do what most people think they should.

Just my opinion - dash bling.

 

[Rhinoman]

Fordem is correct, a narrow band O2 sensor like the original can only really read rich or lean. A heated O2 sensor will come up to temperature faster but I wouldn't recommend wiring the heater to the ignition, the heater should only be switched on when the exhaust gasses have already given it some heat, if the heater element is subject to rapid heating then it can crack. As a rough guide an OEM ECU usually switches on the heater around 25 seconds after start with the engine at normal operating temperature.

 

[SAMMYJAMMY]

My O2 sensor is old, I thought about cleaning it, but shouldn't I see a change in the rich and lean when I play with the mixture when it is up to temp.

 

[Rhinoman]

Yes you should do. If it runs rich all the time the sensor will get contaminated, you could try a new O2 sensor.

 

[SAMMYJAMMY]

I half to wait to get the money to replace it but I want to try cleaning it first, because I found some videos of the same narrow band gauge I have and it was not just sitting still it move when the car was idling up so I will try to clean the O2 first then replace it if that does not work.

 

[Rhinoman]

Have you got a link to a video?