I just heard the same back fire noise in my 2003 pace arrow, 22000 miles, at the time I heard the noise I was pushing it pretty hard, steep hill, 4300rpms, air conditioning going full blast. I had new plug wires installed 3000 miles ago. Once I reached the top, the noise went away until the next day when traveling again, was pulling a slight hill, 3200 rpms, just cruising along and thought yesterday I had air conditioning on so I turned on the air and right away the back fire noise repeated so I turned off the air and after a minute the noise went away.
Can't believe the problem would be related but who knows?
What are your thoughts people?
Thanks
