Fault Codes

[DennisG]

Fault Code 2311

seems the fault codes I had went away after I got gas and found my gas cap was missing , bought a new one

but now getting P2311




2005 3.7 4x4

 

[73surf]

Hey Dennis
Bad coil pack on number 4 cylinder, start there, , make sure the screw holding the coil pack is tight, , make sure the connection is tight and snapped in place, , , you may want to swap number two and four coil pack and see if you get a different code, , ie, a code pointing to number two coil pack. , , then you know it's the coil pack
This code has nothing to do with the gas cap, , ,
Keep us posted

 

[LibertyTC]

Try a new plug in #4 to start with....Jeep likes new plugs gapped properly every 30k!
Then clear code / onto moving coil packs if need be...

 

[DennisG]

Replace plug twice and had 6 extra coils from another jeep tried 4 of them still got code and won't go over 35-40 mph bucking

 

[LibertyTC]

If it is not the plug or coil, onto injector related, could be dirty or malfunctioning.
Fuel pressure test psi readings, bad gas..add some star- tron fuel treatment.
What scanner are you using?

 

[DennisG]

OBII scanner, got gas and it's fresh

will check injector next

 

[CactusJacked]

That (ignition coil circuit) code has nothing to do with fuel delivery, don't bother messing with the injector etc. The likely causes are a bad spark plug, coil, a broken or shorted out (grounded) wire in the #4 coil harness, or a poor connection with that harness. Look at a wiring schematic, trace the harness back to the PCM, and check the connections there. Also, what brand/type of spark plugs did you put in?

 

[DennisG]

autolite double platinum are the new ones

 

[Leeann]

Replace them with NGK or Champion coppers. That's what the engine was designed for and that's what runs the best.

 

[tommudd]

autolite double platinum are the new ones

Thats what someone stuck in the 03, ran bad until I switched to the right plugs they were junk IMO

 

[CactusJacked]

And that's why I asked, suspected the wrong plug(s) might be the culprit. Want to take those out of the equation.

 

[DennisG]

same plug I have in all my other cars and jeep for years

 

[CactusJacked]

same plug I have in all my other cars and jeep for years

And yet, here you are having ignition issues with yours. The recommended copper plugs are tried and true. Others have had running issues with their Liberty when not using copper plugs, which is why I mentioned them.

 

[DennisG]

6 new plugs NGK's still the same!

 

[DennisG]

plugged the plug and hooked up the coil and turned it over , no spark coming from the plug.

 

[CactusJacked]

The likely causes are a bad spark plug, coil, a broken or shorted out (grounded) wire in the #4 coil harness, or a poor connection with that harness. Look at a wiring schematic, trace the harness back to the PCM, and check the connections there.

At least you now know it's not the plug, and not the coil, unless all 4 of the test coils are bad. You're left with not getting power to the coil, did you check the coil harness yet?

 

[Aztimer2]

Replace them with NGK or Champion coppers. That's what the engine was designed for and that's what runs the best.

Which NGK plug is best? Part #?


Sent from my iPhone using Tapatalk Pro

 

[Dave]

Replace them with NGK or Champion coppers. That's what the engine was designed for and that's what runs the best.

^^^this. Check your emissions sticker on the front radiator cross-member. Mine is an 05 and says---ZFR6F-11G. That is the copper core NGK#. They should be pre-gapped at .040 but I always double check cause I'm **** after finding one set wrong a few years back.

Dave

 

[Leeann]

My '05 also says NGK ZFR6F-11G

 

[ltd02]

I always double check the gap too!!!