89 eating o2 sensors
#31
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DC volts on the 20V scale. Black to ground. Red to power for O2 sensor.
#32
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Thanks Cruiser. I just put another 02 sensor in yesterday cause my rig started idling crappy again...same thing as when I started thread. It fixed it, but I know that in a couple thousand miles (if that) the sensor will die again. The sensors seem to be prety black and sooty when I pull them out...I pulled plugs a couple times just for fun, but they look normal. It will pass smog and all that but this thing is just going thru O2 sensors like candy. Not sure where to go from here.
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So Im not 100% sure, but I did test for power...if I did it right, it shows 10-11 volts..kinda fluctuating, but not sure if it was me moving around or actual voltage. Had engine running btw.
What happens when it does not have full 12 volts?
What happens when it does not have full 12 volts?
#34
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You must have 12 volts or so to the red wire and a good ground from the black wire to chassis.
Won't work well if the heater doesn't work.
Try this:
Meter on ohms, plug disconnected, plug to sensor. Red lead to red wire and black lead to black wire. What reading do you get?
Won't work well if the heater doesn't work.
Try this:
Meter on ohms, plug disconnected, plug to sensor. Red lead to red wire and black lead to black wire. What reading do you get?
#36
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#38
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#39
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Ok, I stuck red probe into middle of plug black wire , held black probe to the driveline actually,...got 4.5 ish.
Probed outside black wire same way... (I think its black cant really tell) ..got about 4.0.
Probed outside black wire same way... (I think its black cant really tell) ..got about 4.0.
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#42
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Have you done Tip 5?
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#45
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Well its 104 degrees today and I did a little more
messing around, not much but also ohms tested CPS etc. best I could. Not sure Im doing it right but kinda fun learning. Tested out at 1 then dropped to 0. I looked at my dipstick tube grounds today again as well...there are 2 ground wires with eyelets there, as well as my negative battery cable..all on the stud on the block. Does that sound right? Should neg batt cable go somewhere else? I recleaned everything there and put it all back. I dont see anymore grounds in that area. Cruisers tips indicated that there are grounds at dipstick tube...then to move forward of that and there are more grounds? I dont see any?
messing around, not much but also ohms tested CPS etc. best I could. Not sure Im doing it right but kinda fun learning. Tested out at 1 then dropped to 0. I looked at my dipstick tube grounds today again as well...there are 2 ground wires with eyelets there, as well as my negative battery cable..all on the stud on the block. Does that sound right? Should neg batt cable go somewhere else? I recleaned everything there and put it all back. I dont see anymore grounds in that area. Cruisers tips indicated that there are grounds at dipstick tube...then to move forward of that and there are more grounds? I dont see any?