Oxygen Sensor on Intake?

[Freddie's Buick]

Hello everyone!

I 've been struggling with what to do about the oxygen sensor on my home made single exhaust/header design. Where do I tap for the oxygen sensor?

On the drivers side of my header design, it bends at 45 degrees and welds straight into the passengers side pipe forming the 'Y'.

If I tap at the 'Y' I would have to extend the sensor wires by at least 4 feet. I don't like this so I am thinking of another idea.

Why not tap into the intake manifold right by the EGR valve port? This is were the exhaust gases are routed and stored for combustion dilution.

Has anybody ever thought about this or am I lossing my mind?

Any ideas folks?

 

[fc227]

That’s a tuff one. I don't think it will work on the intake because you are not getting the true exhaust gas passing by the sensor.
That’s my opinion. Any other thought's guys & girls?

 

[b4black]

Won't work. The EGR only recirculates cruise. Nothing at idle.



You're gonna need to get it close to the stock location. Exhaust temps effect the sensor output.

 

[Freddie's Buick]

Rich,

I know that the sensor must have at the very least 600 f in order for it to give off a signal. But should'nt freshly burned exhaust be hot enough?

And is'nt fresh exhaust gas stored in the intake's plumbing for as long as the engine is in idle or cruise?

 

[b4black]

The exhaust oscillates between rich and lean on a second by second scale. The stored exhuast gases in the intake won't be any timely indication of the current richness/lean-ness. While your idling at a stop light, it will be reading the same exhaust gas for a minutes or so. In that time. it should have gone rich-lean-rich-lean many, many times. It's a feedback control system, it needs real time flow going over it.


Making a 4' extension wire has to be easiler than drilling and tapping the intake. Get the make and female connectors from a junkyard and re-solder them to a new piece of purple wire.

 

[Freddie's Buick]

How about tapping into the collector before the 'Y' on the passenger's side header?

 

[b4black]

That would work provided the right and left banks of the engine are equal. Isn't the oxygen sensor only on one side of a NA engine from the factory?