This is the first manual trans one of these that I have done and have been chasing this for a few weeks. I've done a MAF and VE tune only to find it to lean out at idle. Jumping around from 14.1 to over 18 AFR. Higher RPM seems to be more stable and expected. The attached scan shows it taking some time at idle (somewhat rich) then leaning out. It feels like an unmetered air issue but have sprayed the engine down well around intake, vac lines, brake booster, etc. Found no idle change. To note, when I tune out the VE table and only run MAF, the issues seems to go away? Maybe it's a coincident or maybe my tune. I'll attach the last tune as well. The low end of the VE table is ridiculous but only way to keep it somewhat stable. Any help/guidance would be much appreciated.
Your wideband doesn't match the narrowbands. Since the PCM is in closed loop, the wideband should read around Stoich at idle and part throttle. Your wideband is reading much leaner.
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