Can Welding Kill O2 Sensor

[MstangsBware]

Pulled my rear header to weld up a crack. I left O2 sensor in while welding and now I am seeing poor MPG. Can welding with sensor in ruin it? Used a 110 wire welder with flux wire...

[91cavgt]

Pulled my rear header to weld up a crack. I left O2 sensor in while welding and now I am seeing poor MPG. Can welding with sensor in ruin it? Used a 110 wire welder with flux wire...

How close was the O2 sensor to where you were welding? Please tell me you at least unplugged the O2 sensor when you welded.

[OrangeChevyII]

No

[MstangsBware]

How close was the O2 sensor to where you were welding? Please tell me you at least unplugged the O2 sensor when you welded.

The header was off the car when welded..I did leave it in the header and was welding pretty close to it....If MPG does not improve I will swap it with a spare and see. I had the battery disconnected during so PCM may just need a few tanks to relearn..

[talisman]

No

lol.


Excessive heat can kill any electronic sensor.

[MstangsBware]

lol.


Excessive heat can kill any electronic sensor.

If it ends up being the O2 then this is what killed it. I didnt not think to remove it and I was welding right above and around it. MPG did improve a bit on second tank of gas.

[Fastfox86]

O2 sensors are subjected to extreme heat all the time. I wouldn't think a welder would mess it up. If it's old it could just be coincidental that it was messed up. If you bumped or banged the part that sticks out of the header while removing it, that could mess it up. Good luck

[91cavgt]

Or like you say, the computer may need time to relearn the fuel and ignition tweeks. It all depends on the car I would say, and just how close you got to the O2 sensor.

I don't have any personal experience on a Mustang in this senario, but on my old SRT-4, you had 2 choices to get things back to normal after you reset the computer. Either do a full throttle run from about 40 to 140, or wait about 2 or 3 tanks of gas till the ignition timing was back up to where it was before. The retarded ignition timing would give bad fuel economy, but doing a full throttle run from 40 to 140 wasn't exactly saving any gas either.

[91cavgt]

O2 sensors are subjected to extreme heat all the time. I wouldn't think a welder would mess it up. If it's old it could just be coincidental that it was messed up. If you bumped or banged the part that sticks out of the header while removing it, that could mess it up. Good luck

The highest stock EGTs I have seen on any stock car was 1720 degrees. In order to melt metal and bond 2 metal parts together via welding, temps can exceed 5000 degrees. Suddenly 1720 degrees doesn't seem too hot!!

[MstangsBware]

Or like you say, the computer may need time to relearn the fuel and ignition tweeks. It all depends on the car I would say, and just how close you got to the O2 sensor.

I don't have any personal experience on a Mustang in this senario, but on my old SRT-4, you had 2 choices to get things back to normal after you reset the computer. Either do a full throttle run from about 40 to 140, or wait about 2 or 3 tanks of gas till the ignition timing was back up to where it was before. The retarded ignition timing would give bad fuel economy, but doing a full throttle run from 40 to 140 wasn't exactly saving any gas either.

Time will tell...The more I think about it I am pretty sure sparks/metal probally fell on/into the sensor so it might have went South. MPG went from 25 down to 18 on the first tank but this morning fill up showed 20 so it did improve. Should know by the 3rd tank...This is on a modded L-67 and not a Mustang but I am sure it works the same...

[91cavgt]

Time will tell...The more I think about it I am pretty sure sparks/metal probally fell on/into the sensor so it might have went South. MPG went from 25 down to 18 on the first tank but this morning fill up showed 20 so it did improve. Should know by the 3rd tank...This is on a modded L-67 and not a Mustang but I am sure it works the same...

Yeah, if it already came up 2 mpg then I'd give it one more tank to see how it does. If it's not back then go ahead and change it out.

[turbostang]

The highest stock EGTs I have seen on any stock car was 1720 degrees. In order to melt metal and bond 2 metal parts together via welding, temps can exceed 5000 degrees. Suddenly 1720 degrees doesn't seem too hot!!

I can absolutely promise you that your method of thinking is 100% incorrect. First, steel melts at around 2500*. Tig welding is around 3500* at the tip, and MIG welding is generally around 3,000*


Welding is much more localized heat, and if you're welding that close to the sensor that you have to inquire about it - it's too close.

If the current rippling through the sensor doesn't fry it, the heat will - I promise you that.

Why does innovate sell "heat sinks" made of copper for O2 sensors?

hint: They overheat.

[talisman]

Thanks for saving me time, Brooks.

[turbostang]

Thanks for saving me time, Brooks.

No problem Eric!

[91cavgt]

I can absolutely promise you that your method of thinking is 100% incorrect. First, steel melts at around 2500*. Tig welding is around 3500* at the tip, and MIG welding is generally around 3,000*


Welding is much more localized heat, and if you're welding that close to the sensor that you have to inquire about it - it's too close.

If the current rippling through the sensor doesn't fry it, the heat will - I promise you that.

Why does innovate sell "heat sinks" made of copper for O2 sensors?

hint: They overheat.

Yeah, I guess I am 100% wrong here.



I performed a quick search which yielded these responses;

http://hypertextbook.com/facts/2003/EstherDorzin.shtml

http://www.millwrightmasters.com/School/arc_welding.htm

http://www.bortech.com/pdf/english/c...ngproblems.pdf

http://www.millerwelds.com/resources...um-Ron-Covell/

TIG welding produces temperatures up to 35,000 degrees Fahrenheit, yet this concentrated heat can be precisely controlled and directed.