1st guess is leaky valve seals. If this is the case, oil is seeping past the valve seals while the car is just sitting. Then when you start the car, the oil that has seeped into the combustion chamber is buring.
Trouble code P0402 means: Exhaust Gas Recirculation Flow Excessive Detected
Exhaust is overheating the starter, starter may be going bad or exhaust could be starting to plug up and getting to hot near manifolds
Unburned fuel in the exhaust system causes the backfire from the exhaust pipe.
Water vapour due to condensation in the exhaust pipe.
It is timed incorrectly or plug wires are installed incorrectly.
Injectors, timing, low cylinder pressure.
Trouble code P0402 means: Exhaust Gas Recirculation Flow Excessive Detected Replace EGR valve
What causes the change oil light to stay on after starting for 2 to 3 minutes maybe longer on a 2006 chevy equinox 3400 engine.
Excessive wear, or lack of oil. Or both. Generally lack of oil is what causes the excessive wear.
Excessive revving of an engine causes overpressure in the crankcase. It causes unhealthy expansion in the pistons and the valves.
The foods you eat.
No