VStar650CL wrote: ↑Fri Aug 12, 2022 4:55 pm
The P0448 is probably coincidental, it means the ECM tried to open the Evap Vent Valve (probably to purge while running) and didn't get any response from the pressure sensor. The culprit is usually a stuck valve or a full/flooded Evap Canister. It won't be electrical, that would give you a P0447.
Extreme heat under the car is a bad sign, it probably means unburned fuel hitting your Bank2 cat. That most likely means the ECM is misdiagnosing the lean condition and dumping too much fuel into the mix. If your M has the dual MAF's, the first thing I'd check is for debris in the one on Bank2. It's also possible your A/F (front O2) sensor is malfunctioning and causing a non-stoichiometric run condition.
Thanks as always sir. I guess I'll have to monitor for a bit to see if this comes back. Car is due for brakes, brake fluid, oil, air filters, cabin filter and PCV all in around 1kmi (when I actually hit 140kmi, I'm a hair under).
If it does, I honestly wouldn't be surprised that the top O2 sensors (have no idea if they are upstream or downstream - those terms always confuse me lol) are out. Don't O2 sensors last like 110-120kmi on average? I changed my bottom ones 2 years ago at like 130kmi so wouldn't be surprised if my top ones are out. But last I remember, those are an absolute pain to get too (especially considering I don't have a lift anymore)...so that'll probably be like a $1k trip to the dealer I'm guessing.