I don't see a 3.8 Liter engine listed in my manual, but I do see the following listings: 4 cyl; 2.2L, 2.5L, and 2.3 L (Quad 4) firing order = 1-3-4-2
V6 cyl; 2.8L, 3.1L, 3.4L - firing order = 1-2-3-4-5-6
V6 cyl. 3800 firing order = 1-6-5-4-3-2
Cylinders are numbered from the drive belt side to the trans. Side as follows: front = 1-3-5
rear = 2-4-6
Hope this helps.