Cylinder misfire?

[USJeepFeMail]

Help!.... when I take off my Jeep feels like it’s in low gear and running hard. I took it to AutoZone to get a code reading and the codes it came back with is
P0304-cylinder 4 misfire
P0601-internal control module memory check sum error
P0204-injector circuit/open - cylinder 4
P0455-evaporative emission system leak detected (gross leak/no flow)

 

[CharlesHS]

P0204 and 0304: Check the electrical connector for fuel injector No. 4. there may be a dirty or loose connection.

P0601 in most cases means the PCM has gone bad. This is possibly due to a short-circuit inside the PCM. Or, if you disconnect the wires/connector from the PCM while the battery is still connected, that may also cause this code.
With a P0601 OBD-II trouble code, the most common fix is to replace and reprogram the PCM. In a few cases the dealer may be able to reflash the PCM and get it working. But more than likely the PCM will need to be replaced and reprogrammed (we recommend you take it to a dealership for this). The good news is it *may* be covered under your emissions warranty. So even if you're out of bumper-to-bumper warranty or powertrain warranty, check your warranty guide or dealer to see if this is covered.

P0455: Leak in a emissions line or component