Yes, +1 ^^^
4.0l SOHC engine has a Knock sensor under the intake manifold, these do fail.
This engine has 9.7:1 compression ratio so "they" had to add a knock sensor because it WILL ping/knock(pre-ignition) on 87 octane.
The knock sensor detects the pre-ignition(before you can hear it) and the computer retards the spark timing so spark plug ignites fuel before it can self ignite.
This represents a loss of power and if knock sensor was intermittent it could fit those symptoms.
These are a PITA to replace, lol.
Clean the MAF sensor, dirty MAF sensor will cause "bucking", which sounds similar to your description.
Long shot is TPS(throttle position sensor), this sensor tells the computer if gas pedal is being used and in what position it is in.
This sensor works like a light dimmer or volume control a simple rheostat(variable resistor)
Computer sends it 5 volts
TPS send back under 1 volt if your foot is off the gas
TPS sends back above 4.5 volts if gas pedal is pushed down to the floor.
So gas pedal at 1/2 way might be 2. 15 volts, 3/4 3.5 volts, ect....
Now if there was a worn spot on the TPS, the volt might suddenly drop, so computer thinks you took your foot off the gas, then voltage jumps back up where it should be so you get a "bucking" in the vehicle like you where pumping gas pedal only a faster response.
TPS is easy to test with volt or ohm meter, they rarely fail, but rarely is not never, lol, long shot but not a no shot.
9 out of 10 sensors, or controls, replaced by DIYers were not broken, so never replace anything without testing it.
And just FYI, 6 out of 10 sensors replaced by professional mechanics were not broken, lol, but I think some of that is just padding the bill.
Last edited by RonD; 06-17-2015 at 09:13 PM.