Infamous P0171, I need help on this one

[im2bad4ya]

So I put JB weld on the manifold hairline crack and was good for a while, but after a few days my code came back. My exhaust has no leaks. I'm pretty convinced I just have a bad O2 sensor. Unless someone else may have an idea of where to look or what the problem could be.

 

[PSUENGR]

Did you check the JB weld job again? Doesn't seem like a coincidence that when you filled the crack the light went away for awhile.

 

[Velocifero]

I think you need to replace that anchor of a manifold, I'm not sure if JB Weld is going to hold up in this situation, there are a lot of forces working against that solution. After other attempts, did the code come back immediately? I tend to agree that it is awfully coincidental that it remained off for said period fo time and then returned, that being if the other repairs immediately produced a code and this was delayed. I know some codes take a cycle or 2 to show up.

 

[im2bad4ya]

JB weld looks good. When I tried other methods (tighten up all the intake pipes, sealing the fuel injectors, etc) they all worked for a while, this time around it's been the most time before the code came back, but I'm just gonna replace the O2. I hate solving a problem by blindly replacing things but with everything else I've seen, it might be the way to go in replacing it.

 

[im2bad4ya]

The code went away on its own, before I could even order a new O2 sensor or anything, IDK what to make of it, I'll update if anything comes up