2004 Chevrolet Malibu 2.2L P0601 Internal Control Module Memory Checksum Error - Won't Start, Gas Smell from Exhaust

My friend owns a 2004 Chevrolet Malibu with a 2.2L engine, estimated at around 100,000 miles. Recently, the vehicle triggered a P0600 code (confirmed as 'Internal Control Module Memory Checksum Error' on the OBD-II scanner), which initially appeared to be P0801 but was corrected by the device. This error first occurred about four months ago and was cleared at the time—however, it reappeared tonight. The car now fails to restart: after starting, it ran for approximately 50 feet before stalling completely and will not start again. Upon inspection (while parked in a restaurant lot on Sunday night), I noticed a strong gasoline odor coming from the exhaust pipe—an indication of possible fuel system issues. We recently replaced two loose spark plugs; this has been over a year since the last plug replacement. After changing the plugs, the engine started momentarily but then failed to restart. The 2.2L engine uses an ignition coil assembly secured by four bolts for all four cylinders. I'm seeking advice on how to properly inspect the ignition coils and whether they could be contributing to the failure. Additionally, there was a prior P0101 code ('Mass or Volume Air Flow A Circuit Range/Performance') detected. I plan to borrow a fuel pressure gauge in the morning to test for low fuel pressure—hoping this is a simple fix. Could the P0601 error be related to the engine not starting? Is it possible that the ignition system, fuel delivery, or exhaust leak are causing both the stalling and the gas smell? Any insights on diagnosing or resolving these issues would be greatly appreciated.