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View Full Version : Are my O2 Sensors Acting Strange?



ferocity02
February 11th, 2013, 06:20 PM
Idle log is attached. Someone said that my O2 sensors are lazy, not switching fast enough, and should achieve higher voltages. In the attached log they range from 35-777mV and 43-799mV. The log looks a bit different than the one shown in the sticky. The sensors are only 1 year old with 10K miles, they were new Delphi units when installed.

The attached log is a hot idle. Only weird thing is that the TPS is 0.4% in the log because my cruise control cable was too tight. With TPS of 0% the O2's look the same.

Could a poor tune cause them to act this way? The tune is a mail order but the truck got heads and cam since the tune and had not been retuned yet.

14552

joecar
February 13th, 2013, 04:26 AM
Hi Ferocity,

That pic looks better than the one I saw on LS1tech.

Do this:

set the scale max of the HO2Sx1 charts to 1000 mV (on the bottom chart go rightclick->Properties, then for each of Series 1 and 2 set the max value to 1000 mV, save the chart);

then take log of steady cruising at 30-40 mph (engine fully warmed up).

The Alchemist
March 6th, 2013, 06:34 PM
Looks normal to me. You really need to take that with a grain of salt as sample rate vs number of logged pids can make the on screen samples look a bit jumpy or jerky. Scoping them with a high speed scope during driving can give a much more accurate picture of what they are really doing.
Mike

joecar
March 7th, 2013, 04:23 AM
Mike has a good point...

this is why the pid channel count (see bottom of PIDs and Data tabs) should not be greater than 24 (to maximize the sample rate).