Reading 02'S with meter
11-14-2004, 09:38 PM
#1
Reading 02'S with meter Simple question.
Is it possible to read o2 voltage with a voltmeter? I thought about runninga set of leads in the car and hooking them to my meter to check voltage. Kinda ghetto maybe, but shouldnt it work? If so, does anybody know which wire nees to be tapped?
Are wideband o2's direct replacements?
Is it possible to read o2 voltage with a voltmeter? I thought about runninga set of leads in the car and hooking them to my meter to check voltage. Kinda ghetto maybe, but shouldnt it work? If so, does anybody know which wire nees to be tapped?
Are wideband o2's direct replacements?
Last edited by Full-Force; 11-14-2004 at 09:54 PM.
11-14-2004, 10:05 PM
#2
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Originally Posted by Full-Force
Simple question.
Is it possible to read o2 voltage with a voltmeter? I thought about runninga set of leads in the car and hooking them to my meter to check voltage. Kinda ghetto maybe, but shouldnt it work? If so, does anybody know which wire nees to be tapped?
Are wideband o2's direct replacements?
Is it possible to read o2 voltage with a voltmeter? I thought about runninga set of leads in the car and hooking them to my meter to check voltage. Kinda ghetto maybe, but shouldnt it work? If so, does anybody know which wire nees to be tapped?
Are wideband o2's direct replacements?
They stock O2 swing from 0-1 volt many times a second. It would be almost impossible to make sense of the output on a standard volt meter. A DVM would just constantly be auto calibrating and an analog meter might not respond fast enough to the voltage fluctuations. You can use a volt meter to check an O2 sensor for it's general health but it is not really any use for actual monitoring. The LED A/F guages you see that connect to your stock O2 sensor wires basically do what you are trying to do just illuminate certain LED's depending on the input voltage. If < 500mv it goes towards the lean side > 500mv it goes to the rich side of the LED's. (Lean and Rich) are widely variable using Stock O2 sensors as well. It could be from 10.5-17.1 and it may not show that much difference in voltage.
Wideband sensors work off a totally different technology and require a specia l driver/control module that heats,calibrates,etc... They will fit in the bungs as most O2 sensors are the same size but they are not compatible with our VCM at all. You can purchase a LM-1 or Dynojet Commander Wideband controller for 300-400.00 with a sensor. There are many others but just do a search and you will find many post explaining in more detail about the functionality of each system.
11-14-2004, 10:08 PM
#3
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An analog meter will likely also load the line and distort
the output. You want a high input impedance. Back in
the day I used to look at the O2s with a DMM and you
can dope out some things about the state of tune, but
nothing like what you can do with a real scanner.
the output. You want a high input impedance. Back in
the day I used to look at the O2s with a DMM and you
can dope out some things about the state of tune, but
nothing like what you can do with a real scanner.
11-14-2004, 10:12 PM
#4
OK. How about reading EGT's to monitor a/f. A guy that I go to the track with has one of the quickest stock internal GN's and he uses an LS1 MAF sensor and a MAFT to tune it with. He reads EGT from 1 cylinder off each side to gauge where he needs to set the MAFT.
Im just trying to get a simplified version of tuning.
Im just trying to get a simplified version of tuning.