I'm seeing a trend with LC-1's having this issue. Seeing as most of the guys I know locally use the Zeitronix WB's (and a few NGK WB's too) maybe its something with the LC-1's??

 

I hope not,$400.00 down the toilet.

 

I'm sure its a calibration thing if anything. Definitely a decent product.

 

I would more likely say your WB is off. If the NB sensor is fluctuating as you say then it is doing its job. It will never sit around 0.5V, rather it is meant to fluctuate to ensure correct operation of the cat, one way to oxidise the cat, and the other way to reduce it. You can see this by watching the ST trim going back and forth.

As the sensor ages it will become slow to respond but should still swing around the same AFR point. When it is gone it will usually sit on one voltage no matter what the AFR.

 

You probably have an exhaust leak after the primary O2 sensor and before the wideband sensor, this would cause a more lean reading from the wideband but not at the primary sensor. Check the doughnut gasket and the gaskets at your test pipe.

 

Like you said, then it'd read leaner. These guys are seeing *richer* than 14.7 afr.

I just installed my LC-1 last week and will be playing around with it, I'll let you know how mine behaves. I'm guessing either it's either a calibration issue, or a wiring issue. Remember if you have loppy cams, the car might need to run rich to idle nicely. Not that the ecu will do this on its own, but if you had someone else tune your car after cams were installed, this could happen.

 

Too early for me to be posting. I'm an idiot in the mornings.

 

So I logged my car on the way to work this morning. AFR's at cruise were hovering around 14.2, like others mentioned above. I completed the calibration exactly as described in the instructions, leaving the sensor open to atmosphere before installing it into the exhaust.

14.2 is about 1/2 an AFR point more rich than I would expect it to read. Also, I had been tuning my car with just narrowband before and getting values in the .89 and .87 range, I expected my afr's to be around 11.0, but my logged values with the LC-1 are showing closer to 10.5....again, about .5 AFR richer than I was expecting. I know the narrowband tuning is basically wishful thinking, but it's still a fact I wanted to throw into the mix.

This makes me wonder if my gauge is reading .5 AFR on the rich side? I'm going to lean it out and gun for 11.1 AFR on my LC-1, and see how the car runs. Worst case it's .5 AFR leaner than I want it to be and is actually running 11.6 AFR, which is not aweful.

 

What does your wideband read when you are coasting in gear from a high RPM? It should read 20.9, which means 20.9 % O2.

If you want to recalibrate with it in the exhaust, you can do it while coasting in gear from a higher RPM. It's a little easier on a downslope, but it can be done on a flat road, too.

 

20.7 maybe 20.8, if its 20.9 where you are, you have to many plants next to your car.


memory is a poor substitute for knowledge, sorry 20.8 to 20.9 is correct.

 

Sorry I missed this post! I'll give this a try and see what I get.

 

I recently purchased a LM-1 for road tuning and calibrated it in free air as the instructions stated ... it read incorrectly. Finally, I used my normal calibration method for the LC-1 installed in my car (calibrate after the injectors cut while coasting). It now reads perfectly. Give that a try ...

If you aren't sure how ...

It's easiest going down a hill with no traffic
in 3rd or 4th gear, get the revs to around 4000
Let off the throttle and stay in gear (engine braking)
after about 3 seconds the injectors cut ... you can verify in EvoScan
run the calibration a few seconds after the injectors cut
Verify calibration

 

To recalibrate, you just hold down the red button for 3 seconds, but I after that period is the reclibration complete, or does it take 30 seconds (as is kind of suggested by the manual)?

So procedure: coast downhill @ 4000rpms, count to four (to be safe ), hold button down for 3 seconds, release, then continue to coast for...gulp...30 seconds. That is a pretty long time to try and coast!

 

Just a thought, if this works (haven't tried it yet). Perhaps the LC-1 likes to be calibrated with air flowing through it instead of sitting at rest? It's mentioned nowhere in the owner's manual, but just a thought...

 

The LC-1 manual mentions this procedure as an alternate recalibration method (look at the tips and tricks near the end) but recommends the free-air for the initial calibration.

The calibration only takes a few seconds, not 30. Give it 10 or so to be sure ... that's why the hill helps. You'll coast down at a slower rate.