sudden loss of power and backfiring

The fuel pump may be working but you may not have an adequate amount of fuel. On a turn, it the fuel level is extremely low, the pump will draw in air which will cause an engine miss or stall. This will set off the Check Engine lite. The fuel gauge sending units were notorious for failing or giving inaccurate readings on these vehicles. Fill your tank and see if the condition still exists. If it still happens, you will have to look at the engine wiring harnesses for damage.