When using the gas, I get a bouncing feeling like a washboard road, but smooth when in passing gear or coasting. Any ideas?

 

Is it an automatic? Transmission could be slipping, check the fluid level & color.

 

Try the shock test..

make your jeep bounce by pushing down on the vehicle (due to the shocks, it should come back up) do this a couple of times, then stop. if the jeep keeps bouncing up and down, you need new shocks.

If it stops bouncing almost immediately, check your tires, make sure they are not damaged or loose.

Good Luck

 

I noticed today that it gets noticeably worse as soon as it hits 3rd. Also, if I idle for very long it's boggy when I start driving again. I have to go into neutral & blow the pipes out.

 

Check engine light...all 6 cylinders misfire.

 

And it's 4th that gets instantly worse, not 3rd.

 

Good newb answer...

 

So have you started to try and eliminate/pin point the source of the issue? You seem to have pulled codes. I know it didn't just say all 6 cyl are misfiring.

Edit- a decent mechanic with a good diagnostics computer can tell you a lot..

 

I think this is the correct answer.

 

Do you mean cylinder 6 misfire?

 

There were 7 codes, first said multiple misfires & the other 6 were each of the cylinders

 

I'd start w/ some basic troubleshooting. Fuel pressure? Vacuum leaks? Coil? Cap & rotor?

 

I agree with Belvedere, start looking at things common to all 6 cylinders. If you have a rough running engine under load (the hopping?) he's got the appropriate starting points listed.

 

Today the rough engine under load has stopped...completely. Not even a change when going into 4th, which was the worst time. I changed one & only one part. Didn't even take anything off to inspect it. That one part?...serpentine belt. Now the only issues I'm having are a fuel smell & a bogginess when I idle too long.

 

Well the rough in 4th came back but only from 45-55, or uphill, then it smoothes out.