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Thread: Replaced rear 02, still throwing CEL codes? Reply to Thread
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Topic Review (Newest First)
01-29-2014 09:44 PM
seraniko 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.
04-30-2013 01:55 AM
thenorm nailed it!
04-29-2013 09:58 AM
JamesH
Quote:
Originally Posted by thenorm View Post
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:
04-26-2013 06:18 PM
kingbedhead
Quote:
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?
04-26-2013 10:16 AM
JamesH 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.
04-25-2013 08:41 PM
thenorm
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.
04-25-2013 06:57 PM
rent 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.
04-25-2013 10:26 AM
JamesH 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?
11-21-2012 12:14 AM
trackhermit Also something I've ran into as-well check your vaccum lines and make sure none are broken.. also check the large one near the throttle body it's a black rubber hose make sure it's not slit. Mine was.. I know it's not O2 related but it's something I would still check.
11-18-2012 11:11 PM
the chad Thanks for a quick reply. After replacing them the o2 sensor with a bosch replacement, I took a real hard look at all the wiring connections today and located a plug that was disconnected. Now no codes and its running great.
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