hi guyes i have a 01 jeep cherokee and today it just started missfireing and back fireing threw the air cleaner when i hit the gass in drive if i floor ir it goes sluggish then it takes off realy good then backs down again cam i please have some help:banghead:

Is it '01 or '91? How many miles? Which engine/transmission?

First thing...change the plugs. I assume you have a 4L six. A little tricky because you will have to sneak the coil pack rail and the coil packs off in such a way to access the plugs.

I had to use a flex socket for some of the spark plugs.

Any check engine light issue?

im sorry guys its a 91 jeep not an 01 and i just changed the plugs and there is no change it still backfires through the air cleaner dont know why it just started doing that saturdaynight what can the problem be can anyone help me i dont have the money to take it to a shop :banghead::shakehead
ps. no there is no engine light issue

After plugs, consider replacing the cap, rotor, and plug wires.

Were you doing anything specific when it began to backfire?

Did you recently get gas? It sounds like it could be fouled gas. Try a gas drier/additive and see if it helps before you start replacing all of the components.

I had a similar problem and it turned out to be the o2 sensor under the jeep like the o2 and knock wires had been burn and farad fixed them have not had the probe agene might wont to check it