O2 sensor test

[rjkoop]

Tested my O2 sensor. I left the wire hooked up (the PO had already spliced into it to check I guess) and as the car was warming up I got between .1V and .6V. Once car warmed up and idling well I raised the RPMs to 2000 and I got pretty much a solid .85 on the voltmeter. No adjustment of the AFM mixture screw made a difference on the RPM. So does this mean that my O2 sensor is bad?

I do have the O2 sensor removing socket and was able to attach a breaker car and get some good leverage. It felt really stuck and didn't want to break it. I'm thinking about doing a few evenings of penetrating oil, then heating engine up and trying breaker bar again. Is this what most people do? I've heard others just cut the wire and use a regular socket.

Richard

[kilrwail]

I f you know you're going to replace it, just cut the wire and go.

[So Cal Mark]

you need to artificially richen and lean the mixture to see if the sensor responds

[rjkoop]

According to this guide...

http://www.hiperformancestore.com/ljetronic.htm

... the spring (the one held in place by the W thingy) setting controls the mixture. My O2 sensor may be fine because I'm definitely seeing voltage changes from .1V -> .9V. And I get a consistent .85V when warm and at 2000rpm. But I see in this post .9V at 2500rpm may be ok?

http://www.fiatspider.com/f15/viewtopic ... on#p214806

I'm a little confused but I'm thinking it runs well enough. Let's close it up and drive it!

Richard

[klweimer]

A couple of thoughts. If you have a volt meter hooked up, take the car for a drive and see how the O2 sensor responds under different loads. If it's good, it will be moving continuously. Or, for the $20-$30 it takes to replace it, just do that.
Kirk

[rjkoop]

A couple of thoughts. If you have a volt meter hooked up, take the car for a drive and see how the O2 sensor responds under different loads. If it's good, it will be moving continuously. Or, for the $20-$30 it takes to replace it, just do that.
Kirk

Yep. Honestly just worried about breaking the stupid thing when removing it. Otherwise I would have done it by now. I've had a few 'this will take 10 mins to do' morph into a huge pain in the *ss.

Richard

[rjkoop]

Got it running good. A question though...

I marked the position of the AFM tension spring before I adjusted the spring tension wheel. It may have let go and spun loose. I was able to set it back again but am wondering if it could have unspun a full revolution plus some. I don't think so and probably only spun about 14 teeth but just wanted to make sure.

[rjkoop]

Removed the o2 (oxygen) sensor with a 22mm socket and a breaker bar. Actually came off easily which I think is the 1st thing on this car that has done that!

I think it needed to be replaced...


Cut the old wire so hopefully it's easy to get the new wire with the rubber housing through the firewall.

Got it at CAPS in Ottawa... $33. Canadian Tire wanted $85 for the EXTRA SAME SENSOR. Idiots!

Richard