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https://www.autonerdz.com/cgi/yabb2/YaBB.pl General Public Area >> For Non-Technicians >> noisy o2 sensor waveform https://www.autonerdz.com/cgi/yabb2/YaBB.pl?num=1496140077 Message started by caseprobe on May 30^th, 2017 at 3:27am

Title: noisy o2 sensor waveform
Post by caseprobe on May 30^th, 2017 at 3:27am

recently checked my o2 waveform on a Renault scenic 1.6 2001 and found this unusual capture.
Somebody on the pico forum pointed out by zooming in that the noise is not random,could the sensor cable be picking up signals from other cables in the wiring loom

https://www.autonerdz.com/cgi/yabb2/YaBB.pl?action=downloadfile;file=la_2Cmbda_waveform.psdata (657 KB | 303 )

Title: Re: noisy o2 sensor waveform
Post by Tom Roberts on May 30^th, 2017 at 10:17am

The tall shark fins in there are your coil events and the small ones are injection events.

The current for these often present in other inputs as visible voltage drops.

Title: Re: noisy o2 sensor waveform
Post by caseprobe on May 30^th, 2017 at 2:16pm

So not an issue,I must admit its the first time Ive seen this scoping O2 sensor outputs
many thanks