Advice on disappearing nuts

So my 2004 Tacoma's never given me even a hint of trouble until about 30 minutes ago...the CEL came on for the first time, and pointed to a problem with the downstream o2 sensor. When I looked, I found the sensor dangling on by the harness. I'm guessing the nuts must have rusted away...I've seen a few comments here about that happening in some regions. So now I'm wondering what other parts you guys have found that just seem to be more prone to rusting out? I can't get a better look until the morning, but anything I want to be sure to look for specifically?

Thanks in advance. And I'm glad you guys are here. Nobody wants to feel alone after losing his nuts.

 

Spare tire carrier/cable I think

 

It maybe a regional thing to you're area if wet/cold/salted roads, etc: as to how much rust/rusted parts/shit falling off but i don't know what to say about highlighted above...except sucks for you ...to be alone & nutless...

 

Don't mind Doug..... He's just mad cuz he sits on his all the time

 

What bothers me most is the brake and fuel lines.

 

that kind of happened to me two years ago. I started hearing an exhaust leak. looked under and the O2 was "in" the spot but the two nuts had rusted away. thankfully I was able to use a piece of coat-hanger to keep it in place. had the studs re-tapped and two new nuts put on. gotta love the salty north.

other things would be the low hanging fruit. other bolts/lines that sit near or below the frame and in direct splash line of the tires.

 

Eh, I'm married. You get used to it.

Thanks for the suggestions, getting ready to crawl under there now. Oddly, it's not road salt that's the problem though, I'm on the coast in Southern California. Usually we see rust issues on the hood or roof first...or so I thought. Stupid life lessons.

 

Haha I hear ya, honestly I'd just check anything that looks suspect, especially along the exhaust

 

I read the post title, first thought was "It must be cold outside."

 

Go to the hardware store and pick up some stainless nuts. Those should fare better than your previous ones. Not sure what thread pitch/size they are though.

 

They are 8mm x 1.25. I just did this on my T100 - same deal, nuts totally rusted away. I pried off what was left with vice grips, chased the threads with a die, cleaned up the whole area with a wire brush, then put a new O2 sensor and gasket on with new stainless lock nuts. The whole thing took maybe 20 minutes.

 

Doug, you nailed it. Every small fastener from the cat's heat shield back to the exhaust pipe assembly are toast. The ones holding on the heat shield actually dissolved at the touch, which I have to admit...more than a little unnerving.

Thanks again for your help everyone.

 

Sounds like you're asking for marital advice.

 

No worries, yeah anytime you have extremes ( heat from exhaust/cold water,moisture hitting it) this will be your biggest area of rust to develop it seems , ever try unbolting an exhaust manifold thats been on for years ?? Guaranteed bolts will snap & nuts will strip...

 

I haven't had issues with nuts completely falling off, but when I did my lift the nut that held the lower ball joint and tie rod together was so bad that I ended up replacing both of those things because I couldn't get it off, it rusted completely in half, so no wrench was gonna grab it. Also broke off 2 of the lower ball joint bolts. Also some brackets under the hood look like theyre ready to fall off. And the black box over the gas tank has a bracket that is really badly rusted. You look at these things the wrong way and they rot away. At least in the NEK. I've just been plastering the thing with fluid film since I got it.

 

That was kinda my point from earlier , depending on geographics cold,wet,salt roads is the factor for rust, why Toyota skimped on undercoating has been asked .. Before rubberized/plastic vinyl spray on coatings ya have now we used this petroleum based shit that was like paving under carriage with asphalt once it set up...

 

Undercoating is not really a save all solution some people think!!

Sometimes it just makes it worse liquid brine and winter chemicals can get behind the undercoating then is trapped in there.

I just use good paint.

 

Sure it is, just like all apps, it'll only turn out as good as the prep, do shoddy prep & you'll have holes/leaks in/under the skin..