I have a 2007 Chevy HHR, The water pump failed and the car died. I replaced the water pump but the car won't start.
Double check to see if all your plugs are attached fully, all the wires are in place, and do you have to flash the computer to re-program after disconnecting some of the sensors or plugs. Make sure there is spark at the plugs. If you just removed what was necessary to replace the water pump, and it is all back together, it should start.
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