Need some help please. First off, I am in the military over in Puerto Rico. I have a 97 F150 XLT Flareside. It has the 4.6 in it and the exhaust is straight pipes from cats back. Recently, when I romp on the gas, I get a popping coming from the exhaust. When it shifts from 1st to 2nd, you get a flame thrower noise. I have no loss of power or anything. Could this be timing? Also, it occasionally goes into a very rough idle and the check engine light came on once. No codes were found. I have taken it to 3 mechanics and they found nothing wrong. I would like to get this fixed before I ship it to Florida next week and then drive to Ohio. Retirement is nice. Any suggestions will help. Thanks

97 F150 XLT Flareside
4.6 Vortec
Air raid
Complete Sony 2000 Watt system including 2 10's

 

Sounds like your cat(s) have a leak.

Habibi