Yeah, the rear 02 should stay pretty steady, around 0.6-0.7v roughly, I'm not sure how difficult it is to get to the spark plugs on this engine, but if the #2 is leaking down that fast, that cylinder will be flooded with gas. Another check you can do, after the engine is off and the pressure leaks down, if you can pull the #2 plug out, disable fuel by pulling the fuel pump relay or fuse, unplugging the injectors, or the vehicle might have Clear Flood mode if you hold the gas pedal down to the floor and crank, some will disable injectors during clear flood mode. Then put a rag over the open spark plug hole and crank it, see if a ton of gas comes out of the cylinder. That much fuel in the cylinder is going to lower compression as well due to cylinder wash.
I'd be curious to see how it runs with the MAP sensor unplugged. Since I don't see a MAF sensor, some systems will default to known good data when some components fail like this. I don't know if it would do that for a sensor or not, sometimes on GM vehicles it will for failed modules. Here's the OEM injector part number if needed. How is the #2 coil doing, not over heating at all?
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Friday, May 17th, 2024 AT 12:45 PM