o2 sensors
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o2 sensors
I just bought a 95 Mazda with the 2.3 and 5 speed tranny. I bought the truck through a financial repo for $500. The previous owner said that he had just put a new clutch in and now he could not get the check engine light to go off. I put my superchips code reader and got both the upstream and downstream o2 sensor codes. I have not had time to crawl under it to check, but can the two sensor wires be hooked up backwards and sending bad signals to the computer?
The truck also has an exhaust leak so I am wondering if they took the exhaust apart and may not have put the gasket back in the joint.
Thanks,
Anthony
The truck also has an exhaust leak so I am wondering if they took the exhaust apart and may not have put the gasket back in the joint.
Thanks,
Anthony
Post Fiend
Joined: Jan 2003
Posts: 9,748
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From: Connecticut
Could be crossed connectors, although I'm doubting that they would actually reach the other (wrong) sensor. Worth checking, though.
The downstream sensor only monitors the effectiveness of the cat convertor, so if the connector is hooked up properly then either the cat is bad or the rear 02 sensor (or circuit) is bad.
Upstream 02 sensors are the ones that provide feedback to the computer regarding air/fuel mixture. In addition to the sensor/circuit being a cause, an upstream 02 code can also indicate a problem with the fuel trim. What codes were you getting specifically?
You should fix the exhaust leak first as it could very well be contributing to the codes.
The downstream sensor only monitors the effectiveness of the cat convertor, so if the connector is hooked up properly then either the cat is bad or the rear 02 sensor (or circuit) is bad.
Upstream 02 sensors are the ones that provide feedback to the computer regarding air/fuel mixture. In addition to the sensor/circuit being a cause, an upstream 02 code can also indicate a problem with the fuel trim. What codes were you getting specifically?
You should fix the exhaust leak first as it could very well be contributing to the codes.
Posting Guru
Joined: Jul 2003
Posts: 1,978
Likes: 1
From: Alvin, Texas.
I bet the exhaust leak is THE issue contributing to the code.
Thankfully, you asked first before tossing money into sensors and then going on a rampage about how OBD-anything sucks!
You probably have a "lean" code from sensor 1 and 2, so that would be the cause.
Thankfully, you asked first before tossing money into sensors and then going on a rampage about how OBD-anything sucks!
You probably have a "lean" code from sensor 1 and 2, so that would be the cause.
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