P0116 Fault on 2008 Chevrolet Cobalt: No Start, Battery Drain, and Sensor Issues
Hi everyone. I own a 2008 Chevrolet Cobalt and am experiencing significant drivability issues. The car feels sluggish with reduced power, and the check engine light came on. The diagnostic code read P0116 — indicating a problem with either the camshaft or crankshaft position sensor. I first replaced the crankshaft position sensor. After that, the vehicle started and ran smoothly during a test drive. However, the next morning, the battery was completely dead. I installed a new battery, but now the car only cranks — it won't start at all. I then replaced the camshaft position sensor, but the issue persists. The check engine light remains on, though no fault codes are currently displayed. The vehicle shows no signs of starting, and there's no spark or fuel pump sound when attempting to start. I'm concerned about potential internal engine problems or a wiring/grounding issue. Any advice would be greatly appreciated — especially regarding how to perform a crankshaft position sensor relearn procedure if needed. Additional details: The car has a 2.2L engine. I've tried unplugging the coolant temperature sensor (a two-wire sensor typically located in the thermostat housing), but the engine still doesn't respond. I also noticed a strange ticking and thumping noise when cranking, which seems to stop after turning off the key — suggesting possible internal mechanical issues. I'm wondering if this is a sensor-related issue or something more serious like an internal engine failure. Can anyone confirm what steps to take next? Is there a specific scan tool required for relearn procedures? And how do I verify fuel pump operation without a diagnostic tool?
P0116 is typically related to coolant temperature or intake air temperature sensor faults. The fact that you've had two batteries replaced suggests there's an electrical drain — check for parasitic draws or faulty components causing battery depletion.