According to the hand book, it is in the left side wall of the trunk just below the fuel safety switch if it is equiped with one. Im almost sure it is.
relay R1 is for the fuel pump on a 1999 Mercury Cougar
On a 1999 Mercury Cougar : The fuel pump relay is in the Power Distribution Box ( which is " live " ) located in the engine compartment ( it is relay R1 and is one of the black relays )
For a 1999 Mercury Cougar : In the Power Distribution Box ( which is " live " ) located in the engine compartment ( on the drivers side of the engine compartment ) ( relay R1 is the fuel pump relay )
In the relay box with all the other relays.
Your 1991 Mercury fuel pump relay switch is located on the firewall of the engine compartment. The relay switch will be near the center of the firewall.
inside the gas tank
relays just plug in to the fusebox
THE FUEL PUMP RELAY ON THIS MODEL IS ON THE LEFT BACK SEAT SIDE WALL BEHIND THE PLASTIC COVER
The 1994 Mercury Cougar 4.6 liter engine fuel pump relay switch can be found on the firewall in the engine compartment. The fuel pump relay switch will be on the passenger side of the firewall.
fuel pump relay is located on the left side trunk and it is a small panel up towards the trunk.
On a 2001 Mercury Cougar : In the Power Distribution Box ( which is " live " ) located in the engine compartment ( Relay " R 1 " is the fuel pump relay )
On a 1999 Mercury Cougar : The ELECTRIC fuel pump is INSIDE the fuel tank It is installed through an access hole in the top of the fuel tank