Well this has happened a few times only when I have my 97 TJ 4 banger at high rpm's for a long period of time. When I'm on the interstate going 70 at 3000 rpm's and i decrease speed and downshift to usually third (3000 or less rpms in third) My Jeep backfires. Anyone know what causes this? BTW I have a Flowmaster muffler and gutted cat.
Ka-boom...kinda
- Thread starter Jeeppicus
- Start date
Mike Varner
New member
Sounds like something in your ignition (plug wires cross-firing, cracked cap, etc.) Could also be the bushings in the distributor, causing the shaft to move up and down slightly. At least it's a place to start.
Bounty__Hunter
Super Moderator
I've got the Flowmaster and hi-flow cat behind my 2.5L, all it does is cackle when letting off the gas, no backfires. Sounds like something is wrong if it's backfiring.
How were you able to get away with gutting the cat when the TJ uses two o2 sensors, with one after the cat? The computer is getting a signal from the second o2 sensor that the cat is not doing it's job, causing the engine to compensate.
How were you able to get away with gutting the cat when the TJ uses two o2 sensors, with one after the cat? The computer is getting a signal from the second o2 sensor that the cat is not doing it's job, causing the engine to compensate.
