Misfire cylinder 1
 

So It's gone real cold up here in Toronto and I've noticed the Jeep (2007) feeling sluggish and shaky. At idle you can feel the Jeep shaking. Now today the problem got worse, engine light flashing and no power. Managed to limp home the 2 clicks. The rattling coming from the drivetrain once under power is horrible. I ran the diagnostic on the superchips and it came back with a code 305 misfire cylinder 1. Now I'm at a loss as what to check on this thing. Do I just limp it round the corner to Chrysler or are there things I should check first? :(

Have you checked spark plugs and/or wires? Could be time for a quick easy fix.

Any chance you have the lifetime powertrain warranty?

Below is a list of possible causes for P0305, #5 misfire.
Some of the items have a long list of things to check.

[TABLE]
[TR]
[TD="bgcolor: white, align: center"]Possible Causes
[/TD]
[/TR]
[TR]
[TD="bgcolor: white, align: left"]ASD RELAY OUTPUT CIRCUIT
[/TD]
[/TR]
[TR]
[TD="bgcolor: white, align: left"]INJECTOR 5 CONTROL CIRCUIT
[/TD]
[/TR]
[TR]
[TD="bgcolor: white, align: left"]COIL CONTROL 2 CIRCUIT
[/TD]
[/TR]
[TR]
[TD="bgcolor: white, align: left"]IGNITION WIRE
[/TD]
[/TR]
[TR]
[TD="bgcolor: white, align: left"]SPARK PLUG
[/TD]
[/TR]
[TR]
[TD="bgcolor: white, align: left"]IGNITION COIL
[/TD]
[/TR]
[TR]
[TD="bgcolor: white, align: left"]FUEL PUMP INLET STRAINER PLUGGED
[/TD]
[/TR]
[TR]
[TD="bgcolor: white, align: left"]RESTRICTED FUEL SUPPLY LINE
[/TD]
[/TR]
[TR]
[TD="bgcolor: white, align: left"]FUEL PUMP MODULE
[/TD]
[/TR]
[TR]
[TD="bgcolor: white, align: left"]FUEL PRESSURE LEAK DOWN
[/TD]
[/TR]
[TR]
[TD="bgcolor: white, align: left"]FUEL INJECTOR
[/TD]
[/TR]
[TR]
[TD="bgcolor: white, align: left"]ENGINE MECHANICAL
[/TD]
[/TR]
[TR]
[TD="bgcolor: white, align: left"]POWERTRAIN CONTROL MODULE (PCM)
[/TD]
[/TR]
[/TABLE]

Wires look good. Nothing loose. Will check plugs tomorrow. Just wondering why the cold weather would bring this problem to light. Jeep was running great til this cold snap. May be a coincidence. Flashpaq def said cylinder 1 was the culprit. I'll double check the code.

Had same problem. I went to take offending wire off, and it pulled right off leaving the connector on spark plug wires. Replaced wires and plugs and it fixed the problem

I had a similar problem and it ended up being my computer. I would check plugs, wires, coil and computer in that order.

Depending on how old the plugs and wires are id go ahead and spend the money to replace 'em and see if that fixes the problem. In fact you could just swap the wire for another wire on the engine and see if that cylinder misfires instead. I don't know what type of wire you have or how many miles are on them but the carbon core wires tend to wear out on the inside where you can't see. Hope this helps...

Same issue with mine (2010 with 27k miles). Plug failed. As stated, I'd start with plugs and wires first.

My misfire was plugs or wires too. I am forgetting how many miles it was but I think it was 35-40k.

Pretty sure wires and plugs have less than 15000km on them. I'll look over po receipts. I'll swap wire over to different plug and see what code comes up. If it still shows miss in #1then does that point issue towards the Spark plug.