This is more a cautionary tale than a pinpoint advisory on something engine related, but as it'll save you time working on your engine, it should fit.
I've been tuning my car for the better part of the last year. Got the ALDL cable, plugged into my phone, got the moates programmer and tunerpro. I was set! I started logging, and tuning, and logging and tuning. Always chasing some weird little gremlin and using my experience messing with carbs and motorcycles to get me through.
Car never ran quite right.
It would be better but then something else would start moving on the readings. BLM readings would always be around the same. O2 voltages would be sorta rich, but then very lean in highway mode. Ping city. Ping in PE mode. I'd dump the timing -5, -10 degrees, ping almost gone, but still there and car running like garbage.
A few months ago, I found a deal on an AEM wideband gauge and sensor. I didn't think I'd need it for a basic bolt on car. I was wrong.
In the two days since installing it, I have learned more about how the engine is running than in the past year. I was too rich on the AE (9:1+) and fueling was all over the place otherwise! I thought I was lean! Apparently too rich makes knock too!
It was rich on the AE, lean on the VE tables, just plain junk. I'd assumed the flow rate of my injectors, based on the stock tune. The WB sensor proved me wrong quickly.
Car is running better than I've ever known it to run. I think in a couple days I'll actually be done tuning, and I'll be able to close up the passenger kick panel and put a new Delco O2 sensor and take the wideband back out.
It's still a L05 engine, so it'll never be fast. At least it'll be running as good as it can!
TLDR, don't bother tuning with the factory NB o2 sensor. Use a wideband, save a ton of time as well as potential damage to the engine.
P.S. When you go get the wideband, wire it's ground to the negative on the battery. Readings go all over the place if you put it anywhere else. Just save yourself the headache.
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