machz800ps

install lg headers on my car right now do the rear o2 sensors cross over to each pipe ( does driver side o2 thread into passenger side pipe and vice versa) or driver side to driver side and passenger side to passenger side?? car is an 04z so all 4 sensor go back into same location did not pay attention to rear sensors when i removed
Thanks
Steve

dgrant3830

I'm not sure as it sort of depends on how the crossover pipe is plumbed internally. You really need the left forward and rear sensors to be on the same side and the same goes for the right forward and rear. If you don't, you'll have issues for sure.

vettenuts

Front: They do not cross, i.e., driver's side O2 to driver's side plug and passenger's side O2 to passenger side plug

Rear: They do cross, i.e., driver's side O2 to passenger side plug, Passenger's side O2 to driver side plug

machz800ps

ok you are positive and is that your final answer the rears DO cross dgrand3830 says different
THANK YOU
Steve

byronhunter

vettenuts
^
^
What he said!

TN Vette

I recently did TPIS LTs on my 1999 Coupe.

Front sensors do NOT cross
Rear sensors DO CROSS.

dgrant3830

Ok, I'll default to those who know for sure because I don't. I was looking at it from a logical standpoint only. Left front and left rear seeing the same exhaust and similar for the right, on a stock setup, changing that would or could have caused a problem. Now if you reversed the sensors on the rears and kept them on the correct exhaust flow, then there wouldn't be a problem as far as logic goes.

vettenuts

On the stock exhaust, the fronts are vertical and very close to the electrical connection. You can't get them wrong. On the rears, they are angled and the driver O2 runs along the passenger side to the passenger side plug and the passenger side O2 runs along the driver side to the driver's side plug.

Now enter headers, many have the fronts angled similar to the stock rear and there the confusion begins especially since the stock front cable may not reach the correct side without an extension.

TN Vette

The computer uses the front O2 sensors to measure Air fuel ratio and adds or subtracts fuel as required to keep the air fuel ratio correct.

If the front sensors get swapped, the left side will try to control the right side and vice versa and it doesn't work.