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Marcin · Posted: Mon Mar 31, 2003 11:49 am Post subject: Lamba probe output pattern

Hi,

I've question about the lambda probe. I've been measuring the voltage between the probe's output wire and probe's ground wire. So far I know nearly 0 volt stands for rich mixture and nearly 1 volt for lean. What I found was the multimeter showing nearly 0V, then a short pulse to about 0.6V and back to zero. This pattern repeated itself continiously. I don't know how to interpret this. I would expect some oscilations, but more in the mid range when in idle, and falling back to zero for a while only on pressing the accelerator.

Any hints?

Thanks,

Marcin

neo · Posted: Wed Apr 09, 2003 10:48 am Post subject: re

Hi!

You may encounter some problems with the lambda on idle if the engine is cold or the outer temperature is cold because lambda probe works only when hot. Try connecting the multimeter from inside the car and then go for a ride. When driven the engine produces more heat on the exhaust. If the lambda is dead even then, you will have to replace it.

Marcin · Posted: Wed Apr 09, 2003 2:57 pm Post subject:

Hi,

actually I did warm the engine up before my tests, so that shouldn't have caused the problem. I was just wondering if it's the normal response of the probe, that I measured. My car has done nearly 210.000km, so I'm wondering if the probe is ok, or is it ready for replacement. I suspect the car of running rich.

Cheers

Marcin

Scott Sander · Posted: Wed Apr 09, 2003 9:41 pm Post subject:

I thought the probes were only good for 100K. Maybe worth replacing it.
_________________
Scott Sander
'91 Alfa 33 Boxer 16V Monza - Awesome
http://www.sanderfamily.com

timo a. · Guest

The lambda probe is not necessarily broken. It might be that the ECU is not controlling the mixture properly (i don't know if this is common or not).
Anyway the lambda probe is fairly cheap and easy to change so it might be good idea to change it.

BTW. If i'm not mistaken 0V is lean mixture and 1V is rich mixture.