Found broken front O2 sensor stud. (1 Viewer)

[Hog Head]

While under the 80 I noticed that one of the front O2 sensor studs was broken. I know that I have never wrenched it so it has very likely been broken since before I bought the 80 12/05. I called the local Yota parts man and he stated that it looked as if it was not replaceable. Anyone else have to replace one of these studs? I keep getting the low egr flow code even though I have ran all the FSM tests with no failures (also replaced most of the vac lines).

Could a leaky O2 sensor cause the code P0401 to keep popping up?

Thanks, Gene

 

[dgranth]

If you're talking about the threaded bung on the tailpipe, a new one can be welded on as long as there is enough tailpipe to attach it. That has got to be a LOT cheaper than a replacement tailpipe.

The leaky sensor could be related to your trouble code, but I would have expected the O2 sensors to drop a code, too. If they are original, I would recommend replacing them while you're at it.

Good luck.

 

[tarbe]

I can't imagine an O2 sensor issue causing the EGR code (either 401 or 402).

Several of us have recently had good luck curing our EGR codes by pulling the EGR temp probe and cleaning it carefully with fine steel wool. Easy, and free!

Give it a try. It will come out looking black and should be nice and shiny when you finish.

 

[IdahoDoug]

I agree it's unrelated to the EGR code. You can also replace the EGR modulator for cheap and fast, and check/clean the EGR vacuum hoses while your hands are in the area. Much, much higher probability you'll fix the code.

DougM

 

[Hog Head]

Thanks everyone. I figured the broken stud causing the 401 code to be a stretch but thought I would ask anyway. Anybody discover one of these broken?

Gene

 

[thelal]

I've got a broken on as well for last several years. I get a 401/402 on/off and also thought it was O2 (leak) related but not got around 2 investigating/toubleshooting. I just reset and good 4 another 1000+ miles or so.
Will go fix one of these days. On the broken nut I've just put a metal (screw) type clamp around it

 

[Hog Head]

I can't imagine an O2 sensor issue causing the EGR code (either 401 or 402).

Several of us have recently had good luck curing our EGR codes by pulling the EGR temp probe and cleaning it carefully with fine steel wool. Easy, and free!

Give it a try. It will come out looking black and should be nice and shiny when you finish.

Thanks Tim. I pulled the temp sensor and it was caked with thick carbon. Nice and shiny now. Hopefuly it did the trick. I would hate to just start throwing parts at it.

Gene

 

[woody]

they are replacable...I found a replacement stud at Autozone for $1 or so....


remove the O2 sensor

assuming there is something sticking out to get a vice grip on, heat the area where the stud is with your oxy/acet torch

once cherry red, gently persuade the stud out with a vice grip

re-tap

install new stud


course, access to the Ocy/Acet is helpful, as is not having it snapped off flush...

 

[Hog Head]

Thanks Woody. There is about a 1/4" of the stud sticking above the flange. The torch I might have to rent or get for my "birthday".

 

[MTBGUY]

I had one, did what Woody recommended, and it worked well. Good luck!

 

[Wayne]

I was/am having both the 401 and 420 codes.

I replaced the O2 sensors and that fixed the 420 code.

I've replaced the Vacuum Modulator Valve and cleaned the EGR Temp Sensor, neither fixed the 401 code.

I plan on pulling the upper intake and clean it and the TB, and replace the Vacuum Switching Valve.

I'll replace all the vacuum hoses at that time also.

Hopefully, that's fix the 401 code.

Wayne S

 

[Grench]

they are replacable...I found a replacement stud at Autozone for $1 or so....


remove the O2 sensor

assuming there is something sticking out to get a vice grip on, heat the area where the stud is with your oxy/acet torch

once cherry red, gently persuade the stud out with a vice grip

re-tap

install new stud


course, access to the Ocy/Acet is helpful, as is not having it snapped off flush...

Do you remember what the thread sizes were on the stud?

My rear O2 sensor is holding on by one nut and a prayer at this point and getting noisy. I want to have new studs in hand before I remove it. I know one stud is already broken.