At My Wits end! PLEASE HELP!

[LostExpiGirl87]

Hi All!
I'm new here so I don't even know where to start!

I own a 1997 expedition. SHES MY BABY!
About 2 months ago I started having an issue with code P0141!
I changed both downstream 02 sensors and a few miles later the code popped again!
I changed the sensors again, and what do ya know? The code popped again. I set up and appt at the mechanic. He said he checked all wiring and swapped out my Bosh sensors (that I had just put in) for Fisher ones and "my CEL light went off by its self". So I paid their ridiculous fee and went on my way. On my way home.... CEL light came on for the same P0141 code!

I took it to my dads house. He told me to replace my back Cats. Which I did. 160 miles later...P0141 came to visit me again!
My dad found out my head gaskets were leaking. I dropped it off at his house. He did my heads, redid my whole exhaust, shocks, ect ect. After 2 days of him driving it.... P0141 came back to say hello. He's checked all of the wiring over again and all of the wiring looks fine. He's switched sensors from passenger to driver, ect. After dumping $500 into my vehicle, I'm ready to pull my hair out.

PLEASE tell me someone here has had this same problem?!?

 

[Kwik SC]

I'm gonna take a stab here but did you replace the o2 sensors after the head gasket job? The coolant in the exhaust will shorten their life but I find it highly unlikely. I've also read that the threads in the 02 sensor bung may be damaged and that could be causing your issue. It's worth a shot to check that out. If it's not that then it has to be a wiring issue.

 

[LostExpiGirl87]

I might get an "eye roll" response from saying this but, I actually haven't replaced the o2 sensors again since the exhaust work or the head gasket job. Before I went out and spent another $100 on just sensors (for the 3rd time) I wanted to make sure I wasn't missing anything else it could be. Someone else has mentioned maybe my coolant temp sensor?

Also I'm wondering if the expeditions are spoiled and they need specific brands (motorcraft or factory) sensors?

 

[Kwik SC]

I might get an "eye roll" response from saying this but, I actually haven't replaced the o2 sensors again since the exhaust work or the head gasket job. Before I went out and spent another $100 on just sensors (for the 3rd time) I wanted to make sure I wasn't missing anything else it could be. Someone else has mentioned maybe my coolant temp sensor?

Also I'm wondering if the expeditions are spoiled and they need specific brands (motorcraft or factory) sensors?

None of the above.

Coolant temp sensor would throw a different code. Dont waste money on this.

Expeditions are not spoiled. They will take a bosch sensor just as easily a motorcraft. You have a solid diagnostic problem on your hands not easily fixed by swapping parts as you've already realized im sure. What you need to do is two things.

A.) Check for burnt wiring near the connector of the 02's

B.) Check to see if the threads in the 02 sensor bung (the part where the o2 sensor threads in to) aren't damaged and leaking exhaust. A leaky exhaust by the 02 sensor will cause it to throw a code as well.

Something is causing that code to constantly pop up and its not a faulty sensor IMO.

 

[stamp11127]

Multiple threads on same problem. Please see the following for the next episode....

http://www.expeditionforum.com/f73/dear-p0141-lets-break-up-29737/#post239637