1998 Chevy Suburban V8 Four Wheel Drive Automatic 111000 miles
The truck died a couple of months back and I determined the fuel pump wasn't working. I replaced the relay and the pump. Now the pump is not working again. I also replaced the ignition control module. When I turn the key to the on position, the theft deterrent system makes a double clicking noise. I can't recall if that is normal. With the key on, I have closed the contact on the relay and still don't get the fuel pump on. The fuses are all good. I suspect that this is either the theft deterrent system or the ignition cylinder. How do I determine where the fault is before I pour more money into parts. Thanks for any help.