Air/Fuel ratio showing lean???

[streetimagecc]

Hey,

I have a CRX with the D16a6 engine. I have an air fuel ratio gauge hooked up. The guage doesnt seem to work correctly.

When I am at idle the gauge shows it being very lean, its does not fluxuate back and forth from lean to rich like it should, what is the problem?

Also when I hit the gas, the guage will bury in lean, showing me nothing on the guage....whats the problem?? Do I have a bad O2 sensor or is there somthing messed up with my fuel flow somewhere?? please help me out!!

Thanks

[Matt]

if the gauge isn't grounded correctly then it may show an incorrect reading like that.

other then that me dunno

[reese]

air fuel ratio gauges only work on closed loop like idle because there hooked up to the secondary 02 and when your at WOT the ecu runs on pre determined fuel maps not on what the 02 signal is.

[Sniper]

Originally posted by streetimagecc

I have an air fuel ratio gauge hooked up.

it does not fluxuate back and forth from lean to rich like it should, what is the problem?


I'll save PNG the trouble :haha:..........that's the problem...get an EGT......

[Mickee]

just hook up ur air/fule ratio guage to ur system and see it goes when the beat goes pretty neat stuff..... cause like sniper said just get an EGT= Exhaust Gas Temperature...

[MistaFosta]

Theres only one kind of Air/Fuel gauge thats worthy (beside egt) and that is a WIDE BAND o2. It tells you exact readings, just like you get at the dyno. Much more expensive than normal A/F gauges, but much more useful..

Yah, you may have a bad ground though. The worse the ground, the leaner it will read.

[Qx4Beebs]

I had the same problem when I first installed my air/fuel meter, and it turns out that I had it hooked up to the 02 sensor heater lead instead of the sensor. A few cuts and splices later, and now it works fine. To those who say it doesn't work, well sure, it doesn't work well enough to tune your fuel map, but it does give you an indication of when you are running into the lean area and risking blowing your engine. Green=Safe at WOT.

[Wolf]

Do you have a 1-wire O2 sensor or are there multiple wires coming off it? If it's a 1 wire, it could be your O2 sensor is worn out, or you could have a short somewhere between the O2 sensor and the gauge.

[streetimagecc]

I HAVE JUST ONE WIRE OUT OF THE O2 SENSOR. I AM GOIN TO BUY A NEW O2 SENSOR AND RE GROUND THE GUAGE SOMEWHERE ELSE AND SEE IF THAT DOES ANYTHING.

THANKS FOR EVERYONES HELP, I'LL LET YOU KNOW IF IT WORKS.

:cool:

[hybrid2nr]

If it's a 1 wire, you absolutely have to have a good clean ground between the O2 sensor and the manifold as well as the manifold to the chassis ground. Do a voltage drop check with your DVOM set to DC mV from the body of the O2 sensor to the battery negative post while it's running to verify a good ground.

Do you have any exhaust leaks anywhere in the engine compartment, like an exhaust manifold flange leak or a cracked manifold? If you do, the contaminated ambient air around the O2 sensor will definitely cause an altered reading.

It could also be lean-biased from age. Replacing it is the only cure. Any ethylene glycol (flourescent yellow-green) coolant leak into the exhaust, like from a cracked head or blown head gasket will also kill the sensor, not to mention the cat as well. Fix that before you replace the sensor. Silicone sprays for engine detailing are also no-no's as well as silicone sealants that might end up in the exhaust that are not designated as O2 sensor safe.