I have a 1993 Chevy Suburban C1500 with an automatic transmission. Recently it stalled on me when making low speed turns but would restart. I changed the distributor cap, rotor, spark plug wires, and spark plugs and the vehicle continued to stall. The truck finally died on me and I had it towed home where I replaced the distributor (with ignition module) and IAC valve. The vehicle ran fine for weeks until I went to bleed my brakes. While depressing the brake pedal during the bleeding process, the vehicle began to run erratic and stalled. I completed bleeding the brakes and the truck began to run progressively worse with each depression of the brake pedal. As I backed out of my driveway, the truck stalled and I haven’t been able to restart it since. I have fuel spaying in the injectors (perfect spray pattern) but I have no spark from the coil. I am reading 12 volts from the control module to the coil but not spark. The only code I got for the body computer was low voltage to the fuel pump relay. The coil is new, distributor & module is new, and I changed the IAC valve twice. My truck does not have an electronic spark control module under the hood or under the body computer. I suspect the body computer but I was wondering if it would still produce codes and fire the injectors if it were bad. Is there a possibility that the coil I purchased is bad and how common are bad aftermarket parts? I know Delphi had some problems a few years back.