Help interpreting O2 reading vs. BPW?

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JohnnyCaffeine
Posts: 2
Joined: Sun Aug 10, 2025 11:56 am

Help interpreting O2 reading vs. BPW?

Post by JohnnyCaffeine »

New member here, thanks for letting me join! I'm trying to pin down a couple of problems with my 1993 Camaro Z28 (6-speed.) I got TunerPro RT up and running and I'd like to ask for help interpreting the data. My car stutters when I try to accelerate from 1500 RPM. This graph shows BPW (at the bottom) vs. O2 readings (at the top) and RPM (orange), though I think the O2 readings are irrelevant since the car was still open loop at the time? But the problem happens in either open loop or closed loop.

Also, TunerPro is giving me a red "ERROR" in Injector Bank 1 and 2 right from start-up, and Injector Driver 1 and 2 were flashing red "ERROR" intermittently. I do think I have a fuel-related problem, but I'm trying to pin down *what* the problem is. Any pointers would be greatly appreciated. Thanks!
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annawonka
Posts: 1
Joined: Wed Aug 27, 2025 1:08 am

Re: Help interpreting O2 reading vs. BPW?

Post by annawonka »

Welcome to the forum! From your description and the graph, it does look like a fuel delivery issue—those injector errors and BPW spikes at low RPM suggest either a failing injector, wiring issue, or fuel pressure problem. I’d start by checking injector connections, fuel pressure, and any possible ECU/fuse faults before diving deeper.
JohnnyCaffeine
Posts: 2
Joined: Sun Aug 10, 2025 11:56 am

Re: Help interpreting O2 reading vs. BPW?

Post by JohnnyCaffeine »

Thanks Anna, I appreciate your guidance. I've pulled the injectors and cleaned and tested them, they seem to be working well and not leaking. Fuel pressure is 36 PSI, or 44 PSI if I pull the vacuum line off the fuel regulator, I believe these values are correct. The mechanic looking into it agrees it's a fuel issue and that the engine is running very rich. We've replaced all of the ignition system, so unless I missed something with the injectors, it looks like maybe a ECM problem. I pulled the ECM today and shipped it off to G7 Computers in Naples, NY. I'm hoping they find something. If that yields nothing, we do have a local shop that can properly test the fuel injection system better than my amateur self can. Thanks again!
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