2 o2 sensors?
#1
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I was checking 02 sensor prices and I noticed some were upstream and some downstream I've only seen the one infront of the firewall(upstream I would assume). Is there a downstream sensor that I haven't seen?
98 SLE
98 SLE
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Son of a crap! A buddy of mine scanned the car and said my check engine light was on most likely because of a bad o2 sensor. I thought there was only one.I changed the upstream about four years ago .Do you guys know what code a bad o2 sensor would throw?(I assume both o2 sensors would throw the same code)
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There are several codes. No, they are not the same.
0130 HO2S Closed Loop Performance Sensor 1
0131 HO2S low voltage Sensor 1
0132 HO2S high voltage Sensor 1
0133 HO2S slow response Sensor 1
0134 HO2S insufficient activity Sensor 1
0135 HO2S heater performance Sensor 1
0137 HO2S low voltage Sensor 2
0138 HO2S high voltage Sensor 2
0140 HO2S insufficient activity Sensor 2
0141 HO2S heater performance Sensor 2
0130 HO2S Closed Loop Performance Sensor 1
0131 HO2S low voltage Sensor 1
0132 HO2S high voltage Sensor 1
0133 HO2S slow response Sensor 1
0134 HO2S insufficient activity Sensor 1
0135 HO2S heater performance Sensor 1
0137 HO2S low voltage Sensor 2
0138 HO2S high voltage Sensor 2
0140 HO2S insufficient activity Sensor 2
0141 HO2S heater performance Sensor 2
#9
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Ok it turned out to be the downstream sensor I changed that yesterday,but today the check engine light came back on. So I had it checked at Autozone and the guy said it'* code p403 and p404 and then he said possibly a bad EGR. Is there anyway the EGR code could be related to the o2 sensor I just replaced? And is it normal for both 403 and 404 to pop up at the same time?
98 SLE
98 SLE