Header install and O2 sensors
Thread Starter
Instructor
Joined: Oct 2006
Posts: 233
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From: Franklin indiana
Header install and O2 sensors
In the process of installing headers, one side done, finishing tomorrow if possible. What is best for O2 sensors, using fronts in front and extending harness, or using rears in front and changing connector? Is there any difference in the sensitivity? I'll probably get codes even if I install rears, so that won't matter. (no cats)
Pro
Joined: Jan 2007
Posts: 553
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From: Cape Coral Florida
In the process of installing headers, one side done, finishing tomorrow if possible. What is best for O2 sensors, using fronts in front and extending harness, or using rears in front and changing connector? Is there any difference in the sensitivity? I'll probably get codes even if I install rears, so that won't matter. (no cats)
Race Director
Joined: Apr 2007
Posts: 11,152
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From: South Western Ontario
I have no idea where the "you must use the rear in the front" on headers got started but the only reason the rears are useful is the longer harness. However, they don't plug in so you either need adapter harnesses or extend harnesses. If the fronts will work better then use them. If the rears would work better use them.
Le Mans Master
Joined: May 2005
Posts: 6,366
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From: Fort Lauderdale, Florida
In using LG headers, they suggest using the rear sensors in front with their adapter harnesses and then plugging the rear O2 bungs. Next would be to get the rear sensors tuned out. That's how my car is done, as they recommend and it works just fine. My car still passes NJ inspection for emissions, which is all we get checked for nowadays. They don't look at anything else anymore.
Le Mans Master
Joined: Aug 2005
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From: CA.
St. Jude Donor '13-'14-'15
One more vote for using the rear 02's onto the front locations---- Using My EFILIVE data logger I have proven it to myself that the rears do in fact work better----They heat up quicker--settle CLOSER to .450 millivolts (14.68 AFR) on LT headers than the stock front units in closed loop--and oscillate faster than the fronts with LT's
Safety Car
Joined: Aug 2011
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From: Portland OR
One more vote for using the rear 02's onto the front locations---- Using My EFILIVE data logger I have proven it to myself that the rears do in fact work better----They heat up quicker--settle CLOSER to .450 millivolts (14.68 AFR) on LT headers than the stock front units in closed loop--and oscillate faster than the fronts with LT's
With my coated XS Power headers, I have no issues with O2 switching....as far as I know. I used new GM Sensors which are a different design from the originals.
I will say that the position of the O2's isn't much different from stock. No cable extenders needed.
Ron
Race Director
Joined: Apr 2007
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From: South Western Ontario
There are a few different colors used depending on the sensor. You can find different connection patterns on line if you search for the sensor manufacturer. Typically, there are 2 wires the same color for the heater and then a dark colored wire which is the sensor high signal (purple or black for example) and a light colored wire which is the sensor low signal (grey or white for example).
Last edited by lionelhutz; Dec 3, 2012 at 02:42 PM.
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Le Mans Master
Joined: Aug 2005
Posts: 5,375
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From: CA.
St. Jude Donor '13-'14-'15
Did you use new sensors Tom? Or used ones?
With my coated XS Power headers, I have no issues with O2 switching....as far as I know. I used new GM Sensors which are a different design from the originals.
I will say that the position of the O2's isn't much different from stock. No cable extenders needed.
Ron
With my coated XS Power headers, I have no issues with O2 switching....as far as I know. I used new GM Sensors which are a different design from the originals.
I will say that the position of the O2's isn't much different from stock. No cable extenders needed.
Ron
Thread Starter
Instructor
Joined: Oct 2006
Posts: 233
Likes: 3
From: Franklin indiana
Did you use new sensors Tom? Or used ones?
With my coated XS Power headers, I have no issues with O2 switching....as far as I know. I used new GM Sensors which are a different design from the originals.
I will say that the position of the O2's isn't much different from stock. No cable extenders needed.
Ron
With my coated XS Power headers, I have no issues with O2 switching....as far as I know. I used new GM Sensors which are a different design from the originals.
I will say that the position of the O2's isn't much different from stock. No cable extenders needed.
Ron
Thread Starter
Instructor
Joined: Oct 2006
Posts: 233
Likes: 3
From: Franklin indiana
I double-checked, mine have plugged bungs in top of collectors, looks like they will reach also. Wish I would have checked earlier, headers are in place, will have to take trans tunnel plate off to install there...oh well. Did you use rears? If so, do you get codes?
Race Director
Joined: Apr 2007
Posts: 11,152
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From: South Western Ontario
No point since you're not installing cats. I installed them because I had to pass a tailpipe sniffer so I figured why not since they'd give an early warning off a bad cat before hitting the test station. And they don't throw codes with the high flow cats in place. Now, this area switched to a OBDII test so I could likely get away without the rear O2's.
Safety Car
Joined: Apr 2007
Posts: 3,582
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From: SoCal CA
One more vote for using the rear 02's onto the front locations---- Using My EFILIVE data logger I have proven it to myself that the rears do in fact work better----They heat up quicker--settle CLOSER to .450 millivolts (14.68 AFR) on LT headers than the stock front units in closed loop--and oscillate faster than the fronts with LT's
Le Mans Master
Joined: Mar 2006
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From: Lino Lakes MN
Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 328
From: CA.
St. Jude Donor '13-'14-'15
I would never re-wire or cut a manufactured pigtail and adapt it to fit--I've seen too many failures even with the best of"electricians" trying to solder or wire connect pigtails--
Thread Starter
Instructor
Joined: Oct 2006
Posts: 233
Likes: 3
From: Franklin indiana
Well. looks like bungs on top of collectors were plugged for a reason, sensors would hit torque tube there. Will the car make it to the exhaust guy 5 miles away w/o any sensors at all till he can install bungs in another location? Stupid things touch the bellhousing also, going to have to take care of that too.