Autozone are parts salesman not techs. Codes never identify bad part, just failed systems. I will give you the flow chart for this code.
P1494-LEAK DETECTION PUMP SW OR MECHANICAL FAULT
Immediately after a cold start, with battery/ambient temperature between 40 deg. F and 90 deg. F and coolant temperature within 10 deg. F of battery/ambient.
The state of the switch does not change when the solenoid is energized.
Vehicle History and Service Bulletin Investigation
LDP Switch Sense Circuit Shorted to Ground
Wiring Harness Intermittent
LDP Vacuum Supply
Faulty Leak Detection Pump
LDP Switch Sense Circuit Open
Powertrain Control Module
Sunday, June 30th, 2013 AT 7:06 AM