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Old 04-25-2013, 06:57 PM   #21
rent
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I know this will sound strange, but change your spark plugs.

I was running copper core plugs for a while (~10k miles) and when they would get to the end of their lifespan, I would start seeing O2 codes.

I did change my O2 and still got the code. One day I looked at my mileage and thought "Its about time to change those plugs", problem went and stayed away with new plugs.
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Old 04-25-2013, 08:41 PM   #22
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Quote:
Originally Posted by JamesH View Post
I'm getting a similar issue on my '02 SVTF - P0141 and P0136 codes come up, I checked the fuse, cleaned the connections and then replaced the 2nd (post-cat) O2 sensor with a Motorcraft one and the codes come back every time.

This is the first thread I've seen discussing wiring diagrams - can anyone link me to a wiring diagram or identify any trouble areas?
theres another connection in the o2 sensor circuit/engine harness. Ita big plug square plug above the alternator near the firewall. I had the gasket pinched here once and was throwing all sorts of wierd O2 codes. I tracked it down with a multimeter. anyways, check that connection.
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Old 04-26-2013, 10:16 AM   #23
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Thanks guys!

I'll check that connection near the alternator.

It's about time I changed my spark plugs too, I'm not sure how long those funky 4-electrode ones last but its been 2 years since I put them in.
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Old 04-26-2013, 06:18 PM   #24
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Originally Posted by JamesH View Post
Thanks guys!

I'll check that connection near the alternator.

It's about time I changed my spark plugs too, I'm not sure how long those funky 4-electrode ones last but its been 2 years since I put them in.
have u unpluged positive for 10 mins?
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Old 04-29-2013, 09:58 AM   #25
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theres another connection in the o2 sensor circuit/engine harness. Ita big plug square plug above the alternator near the firewall. I had the gasket pinched here once and was throwing all sorts of wierd O2 codes. I tracked it down with a multimeter. anyways, check that connection.
Thanks!!! That seems to be it, I looked at the top near the alternator and found this:
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Old 04-30-2013, 01:55 AM   #26
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nailed it!
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Old 01-29-2014, 09:44 PM   #27
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My motocraft rear o2 sensor lasted for 6k...back to p0141..got the bosch sensor from autozone with 1 yr warranty and hope it last longer than that.
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