clarification of O2 sensor wiring with headers
07-01-2023, 06:00 PM
#1
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clarification of O2 sensor wiring with headers
So I just finished putting my blown Z06 back together with a DSS 3.5" solid driveshaft.
It adds to the vehicle vibration but with a full Billy Boat exhaust (long tubes to tips, cat elements removed) the car's not ever going to be grocery getter smooth.
I can live with a little more vibration, especially if it mean's I don't have to worry about rubber couplers failing ever again.
I reconnected the O2 sensors as I've read on multiple boards... crossed over.
Which ran like $hit and threw multiple codes.
Got to thinking, with stock ex manifolds, the harness is just long enough on each side to reach the short front O2 sensor leads... on the same side of the engine as the O2 sensors.
Harness extenders run down the firewall but end up on the same side of the driveshaft tunnel as the original connectors.
The O2 sensor wires are not crossed when they're correctly wired... the sensor lead from the sensor on the right connects to the harness extender on the right. The fact that the tips of the sensors cross when the sensors are in long tube header collectors means the wires overlap by maybe an inch; I suppose this is what is meant by "cross the sensor wires" but those instructions are terribly misleading to my mind.
Regardless of whether you are facing the front or rear of the car, the sensor lead from the sensor in the right collector connects to the wiring harness on the right side of the driveshaft tunnel. Or better yet, the O2 sensor lead from sensor in the the passenger side collector goes to the passenger side wiring harness connector.
Crossed wires my a$$.
Rant over.
It adds to the vehicle vibration but with a full Billy Boat exhaust (long tubes to tips, cat elements removed) the car's not ever going to be grocery getter smooth.
I can live with a little more vibration, especially if it mean's I don't have to worry about rubber couplers failing ever again.
I reconnected the O2 sensors as I've read on multiple boards... crossed over.
Which ran like $hit and threw multiple codes.
Got to thinking, with stock ex manifolds, the harness is just long enough on each side to reach the short front O2 sensor leads... on the same side of the engine as the O2 sensors.
Harness extenders run down the firewall but end up on the same side of the driveshaft tunnel as the original connectors.
The O2 sensor wires are not crossed when they're correctly wired... the sensor lead from the sensor on the right connects to the harness extender on the right. The fact that the tips of the sensors cross when the sensors are in long tube header collectors means the wires overlap by maybe an inch; I suppose this is what is meant by "cross the sensor wires" but those instructions are terribly misleading to my mind.
Regardless of whether you are facing the front or rear of the car, the sensor lead from the sensor in the right collector connects to the wiring harness on the right side of the driveshaft tunnel. Or better yet, the O2 sensor lead from sensor in the the passenger side collector goes to the passenger side wiring harness connector.
Crossed wires my a$$.
Rant over.
07-01-2023, 09:13 PM
#3
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The rear O2 sensor wires cross over so the driver side O2 sensor will connect to the harness on the passengers side.
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C5 Diag (07-01-2023)
07-01-2023, 10:23 PM
#5
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My rears were deleted from the tune but still in the x-pipes for plugs. Got some real plugs.
Fixed a bunch of bullshit I found while it was apart.
When I finally got to drive it today after it was on the lift for several weeks I was reminded why I did all the work. Love this car.
I have dozens of cuts on both hands and forearms from doing the headers, plugs, wires, etc.
Corvette mechanic hands.
The studs on the coil packs that the covers snap onto are nasty little effers
Fixed a bunch of bullshit I found while it was apart.
When I finally got to drive it today after it was on the lift for several weeks I was reminded why I did all the work. Love this car.
I have dozens of cuts on both hands and forearms from doing the headers, plugs, wires, etc.
Corvette mechanic hands.
The studs on the coil packs that the covers snap onto are nasty little effers