When I drive, the MIL check light pops on, then will go away on its own. This started about a week ago. The car sounds fine, with no power issues. Have gone through more than a tank of gas, so it's not a gas issue and have changed the oil. MIL light will come on at the same time as the ESP light, but the ESP light will go off soon after. Would like to avoid the dealer at all costs. Any ideas?