Obx header O2 sensor

907mge · 01-31-2011, 02:59 AM

Yeah I was wondering about the effects of just having a longer wire alone since mine is extended by about 4ft. to reach. And then with the sensor being so far down versus the oem location right by the head, I think my mpg s are suffering because of it. Its a project for the spring to move it.
How low can the exhaust temps drop in 3ft.?

cre · 01-31-2011, 03:23 AM

4 FEET?!

That's WAY too long. The method you used to extend it may have made it worse too... You never want to solder a low voltage/small signal wire. I wouldn't try extending it more than a foot or damn near.

In three feet exhaust can loose a lot of energy. Think about it this way... on a very free flowing exhaust the air coming out of the muffler probably is still under 200?; It leaves the head around 1400?; Average combustion temps are around 1600-1700?.... That's a BIG drop and VERY fast.

Widebands aren't anywhere near as touchy, but I once had to move one because it was overheating in the stock location... we didn't move it more than a foot and it was fine. The first four feet or so are where the exhaust sees the biggest drop in temperature after leaving the cylinder. But, as mentioned, the heat thing isn't the biggest issue just wire in a heated sensor instead.

The nice thing with widebands is that they're full scale and use a much wider voltage range, a minor drop isn't going to affect much; Narrowbands on the other hand use a signal between .3 and .6 volts to declare an optimum mixture... outside of that range the ECU gets no usable information at all.

Sonyps307 · 01-31-2011, 06:24 AM

If I don't extend it longer then a foot of wire and crimp the wires. Then move the o2 sensor closer to the stock position. U think it would work right then. Also maybe I could go to the junk yard and get the 2 plugs for the o2 sensor and make a extension wire so I don't have to cut my o2 sensor and just plug and play.

cre · 01-31-2011, 07:56 AM

WTF??? Dude... my relatives in Europe speak better English, and the older ones don't speak it. If it's not your native language then I suggest you start using Google Translate, I'm not replying to posts like this anymore.

Sonyps307 · 01-31-2011, 08:17 AM

Here cre do u understand it now

01-31-2011, 03:23 AM	#2
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	4 FEET?! That's WAY too long. The method you used to extend it may have made it worse too... You never want to solder a low voltage/small signal wire. I wouldn't try extending it more than a foot or damn near. In three feet exhaust can loose a lot of energy. Think about it this way... on a very free flowing exhaust the air coming out of the muffler probably is still under 200?; It leaves the head around 1400?; Average combustion temps are around 1600-1700?.... That's a BIG drop and VERY fast. Widebands aren't anywhere near as touchy, but I once had to move one because it was overheating in the stock location... we didn't move it more than a foot and it was fine. The first four feet or so are where the exhaust sees the biggest drop in temperature after leaving the cylinder. But, as mentioned, the heat thing isn't the biggest issue just wire in a heated sensor instead. The nice thing with widebands is that they're full scale and use a much wider voltage range, a minor drop isn't going to affect much; Narrowbands on the other hand use a signal between .3 and .6 volts to declare an optimum mixture... outside of that range the ECU gets no usable information at all. __________________ If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum. If you're so inclined I'm always more than happy to accept tips via PayPal. Tip Jar --->

01-31-2011, 06:24 AM	#3
Sonyps307 Lexus & 550's Join Date: May 2010 Location: Baltimore Posts: 526	If I don't extend it longer then a foot of wire and crimp the wires. Then move the o2 sensor closer to the stock position. U think it would work right then. Also maybe I could go to the junk yard and get the 2 plugs for the o2 sensor and make a extension wire so I don't have to cut my o2 sensor and just plug and play. Last edited by Sonyps307; 01-31-2011 at 08:14 AM.

01-31-2011, 07:56 AM	#4
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	WTF??? Dude... my relatives in Europe speak better English, and the older ones don't speak it. If it's not your native language then I suggest you start using Google Translate, I'm not replying to posts like this anymore. __________________ If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum. If you're so inclined I'm always more than happy to accept tips via PayPal. Tip Jar --->

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01-31-2011, 02:59 AM	#1
907mge 20psi boost Join Date: Dec 2009 Location: Harrisburg Posts: 759	Yeah I was wondering about the effects of just having a longer wire alone since mine is extended by about 4ft. to reach. And then with the sensor being so far down versus the oem location right by the head, I think my mpg s are suffering because of it. Its a project for the spring to move it. How low can the exhaust temps drop in 3ft.?

01-31-2011, 08:17 AM	#5
Sonyps307 Lexus & 550's Join Date: May 2010 Location: Baltimore Posts: 526	Here cre do u understand it now