2005 Hummer H2 P0107 Code: Engine Stalls After Warm-Up - Diagnosis and Fixes

The codes 'EV', 'O', 'OH', 'C', 'CC' are unclear—what do they mean in the context of a 2005 Hummer H2? Why were the fuel sending unit, MAP sensor, and wiring replaced? Was the MAP sensor circuit tested for continuity or voltage faults? Do you have access to a scan tool with data logging capabilities? A running engine can sometimes trigger false MAP codes. When did this start? Was there poor idle performance before the check engine light appeared? Use your scan tool to monitor MAP signal voltage at idle (should be 1–1.5V) and ensure a steady 5V reference from the PCM. Check for loose connections or corrosion in the MAP sensor wiring.

I initially replaced the MAP sensor due to P0107, but discovered significant damage in the wiring harness. I also replaced the fuel pump because I suspected a faulty fuel sending unit—though I now suspect it might not be the root cause. My scan tool shows P0107 and codes like 'EV', 'O', 'OH', 'C'. The vehicle runs fine initially but starts to stall after about 30 minutes of driving. This inconsistency is puzzling. Could a wiring error or poor grounding be responsible? I’ve noticed the idle remains stable for around 30–45 minutes before stalling—any idea why this happens?

How do you reset the PCM after diagnosing an issue with the MAP sensor or related systems?

Disconnect the negative battery terminal for 10 seconds and reconnect to reset the PCM. The P0107 code indicates a fault in the MAP sensor circuit—start by checking electrical connections, including voltage at the MAP sensor (idle should show 1–1.5V) and ensuring a stable 5V reference from the PCM. Use your scan tool to monitor real-time data for MAP voltage during idle. If you don’t have a proper scan tool with live data capabilities, consider upgrading. Also verify that the 'EV', 'O', 'OH', 'C' codes are not related to the MAP sensor—some may be unrelated or secondary.

In addition to voltage checks, ensure you're maintaining a solid 5V reference at the MAP sensor. Back-probe the connection to confirm it's receiving proper power. Also check for physical damage to the MAP sensor seal—cracks or leaks can cause erratic readings and trigger false codes.

I'm now checking the wiring harness connections, ensuring they're secure and properly routed. I'll also inspect the MAP sensor seal and verify that all electrical circuits are intact before proceeding with further diagnostics.

The check engine light is currently off. After re-wiring the MAP sensor (where a wire had come loose), the P0107 code disappeared. However, when I plug in the scan tool, it shows 'MF CC' (solid) and 'OH C', 'EV' blinking. Is this normal? Did I need to complete a 150-mile drive cycle to reset these codes? This week has been extremely frustrating with intermittent issues.

'MF CC', 'OH C', and 'EV'—what do these codes mean in relation to the scan tool output? A 150-mile drive cycle is required for OBD2 monitors to reset, but this does not affect MAP sensor code triggering. The PCM sets a P0107 code when it detects that the MAP sensor voltage drops below 0.20 volts for more than five seconds—this is a direct electrical fault condition.

No longer seeing the P0107 code—the issue seems resolved, though I still see persistent codes like 'EV', 'O', 'OH', 'C'. These may be secondary or unrelated to the MAP sensor.

Apologies—my scan tool shows P0107 and other codes such as 'MF EV O OH C CC' at the top. The sensor appears to be functioning correctly now, but I'm still unsure what these additional codes mean or whether they're related to the MAP system.