I have a BMW E36 320i, of which there are also 4 other engine capacities for the same 6 cylinder engine (323i, 325i, 328i and M3). The 318i is a four cylinder engine and the exhaust is unique to it.
The 320i and 323i have a single pipe from the 2 downpipes of the exhaust headers (via a 2-into-1 junction) all the way to the muffler in the rear. These two models have 1 oxygen sensor (also called a lambda sensor).
The rest of the models have two pipes - one for each exhaust header (each exhaust header has 3 exhaust ports per header and all models from the 320i up have two exhaust headers) that go all the way to the rear muffler.
There are 4 oxygen sensors on these double pipe models - one for each header and one for each catalytic converter (that screws in just before the CC).
I have the possibility of getting a used exhaust system that used to be on a 328i which has 4 oxygen sensors. I would not be using the exhaust headers from the 328i just the exhaust system from the down pipes back, which includes the 2 catalytic converters. So I would only have 2 oxygen sensors to deal with.
My thinking is that somehow I can use the 2 oxygen sensors that are plugged into a box that has a circuit that averages out the two oxygen sensor readings (the inputs) and the output would then be passed on to the car's computer via the regular plug that the sensor normally plugs into (I'm surprised that there isn't a ready-made setup as this would be of benefit to lots and lots of car enthusiasts).
I haven't researched yet how many wires the oxygen sensors from the 328i have or, for that matter, the 320i. But just wanting to know how simple/feasible this would be and whether my thinking is sound on this. I understand that the flow rates of exhaust gases may be different for the different engine capacities but the sensors measure the oxygen content via voltage fluctuations. Hence my post here.
The 320i and 323i have a single pipe from the 2 downpipes of the exhaust headers (via a 2-into-1 junction) all the way to the muffler in the rear. These two models have 1 oxygen sensor (also called a lambda sensor).
The rest of the models have two pipes - one for each exhaust header (each exhaust header has 3 exhaust ports per header and all models from the 320i up have two exhaust headers) that go all the way to the rear muffler.
There are 4 oxygen sensors on these double pipe models - one for each header and one for each catalytic converter (that screws in just before the CC).
I have the possibility of getting a used exhaust system that used to be on a 328i which has 4 oxygen sensors. I would not be using the exhaust headers from the 328i just the exhaust system from the down pipes back, which includes the 2 catalytic converters. So I would only have 2 oxygen sensors to deal with.
My thinking is that somehow I can use the 2 oxygen sensors that are plugged into a box that has a circuit that averages out the two oxygen sensor readings (the inputs) and the output would then be passed on to the car's computer via the regular plug that the sensor normally plugs into (I'm surprised that there isn't a ready-made setup as this would be of benefit to lots and lots of car enthusiasts).
I haven't researched yet how many wires the oxygen sensors from the 328i have or, for that matter, the 320i. But just wanting to know how simple/feasible this would be and whether my thinking is sound on this. I understand that the flow rates of exhaust gases may be different for the different engine capacities but the sensors measure the oxygen content via voltage fluctuations. Hence my post here.
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