The Bosch LSU4.2 wide-band O2 sensor voltage

[dlaing]

Rather than post a new topic, I thought I would ask here as I am using the LSU 4.2 with Innovate LM-1:

Where are people mounting the sensor?

I think it has been asked before, but I am having trouble and I suspect it is too cold.

I tried the sensor on the left and the right, thinking that maybe one side had and air leak, bad valves or something, but both read very high (lamda of about 3, AFR of about 40-50 and fluctuating inconsistently.

I have seen some good numbers at idle if I let it get pretty hot, then open the air bypass screw about three turns which gives me 15:1 AFR. I can then screw it in to about one turn out, which bring the AFR to about 14:1, but if I try to go richer than that the numbers jump back up to 40 or 50 to one ratio.

It holds pretty steady between 14 and 15 at idle, but blipping the throttle makes it jump back up, and I have to let it idle, move air screw out, and then back in.

Weird...

My guess is that sensor is too cold and engine is running too rich to get a good reading.

I checked for intake leaks with propane method.

I physically felt for exhaust leaks and it seems fine, but there is a carbon puff mark at the clamp to the crossover.

I bought the LM-1 with RPM kit and Bosch sensor second hand on eBay.

My other guess is that the sensor is bad.

But it passes every test...

Calibration seems to work with 20.9 appearing.

I breathe on it and it reacts dropping below 20.9 (don't burn your lips if you try this).

I aim an unlit propane torch at it and it drops close to 14.7:1 (this indicates it is functioning correctly)

Here is the placement:

[Cliff]

That placement is fine. Thats where I run mine. The sensors have internal heater.