1-3-4-2
Haynes says 1-3-4-2 You can take a look here; http://autorepair.about.com/library/firing_orders/bl-pontiac-firing-98.htm FriPilot
how to check fuse for horn in a 1998 Pontiac sunfire
See stvndberryhill's answer under 1998 Pontiac Sunfire horn relays. This answer applies to all year models of Pontiac Sunfires.
R134a
check this site------>
Off the water pump
The firing order for a 1998 Pontiac Bonneville 3.8 SE is 1, 6, 5, 4, 3, 2. This engine has the number one cylinder on the right side, in front of the passengers seat.
autozone.com
22 and 17
Yes
the 98 sunfire haz a 57.2 litre gas tank
its already got one