Miss fire

Pull codes first. Next I would not be driving this if the CEL is flashing. You can ruin your catalytic converter and cost you big bucks. You might have to put a medium level scanner on it and pull historical codes if you do not have current or pending codes. I would also look at live data on a scanner to narrow issue

Ok 3 times it shows misfire on cylinder 5 code P0305 is the only code. Only shows 3 times as last weekend I pulled the positive battery cable. Seemed like it helped after 30-40 mile drive but, prolly just me.

Try switching the coil but remember where you put the original #5 and see if issue changes cylinder. If so you need a new coil. A visual inspection of the coil might reveal a split causing electric to arc.

Do not pull your positive off without FIRST taking off negative. If you want to reset computer take the negative off for 10 minutes.

If your issue stays on cylinder #5, then suspect the wiring on #5 coil. Just for peace of mind on the spark plug, you can test it or buy a new one and put it in.

Ok thanks for all the info. First I have to go buy some tools. Working out of state and did not bring tools with me.

Swapped coils and still shows miss on 5. What is the voltage supposed to be on the wires to the coil pack. Since it has 2 plugs per cylinder I do not think with 1 not firing it would make to big of a diffrence.

I wonder if you are having an issue with the infamous Multi-Displacement System.

No idea

When you swapped coils did you clear code? If so I’m assuming you got the p0305 again after 30 miles of driving?

No, I did not clear the code. Just drove and made it start misfire again. Then made the block and had it read again.

Ok an update. Today it missed all the time barely noticeable at idle. I cleared the computer this afternoon and again it felt smooth and strong. Only drove about 9 miles and got on it several times and no missing or check engine light. The last time I got on it it missed and check eng light came on briefly. I'm woundering if this sounds more like a computer issue than a mechanical issue. I have not had the code read yet to see if a different code comes up.

Had code read same code for misfire on cylinder 5. Why would it run better when I clear the brain? MDS starts working again after clearing the brain also.

Have you looked at fuel delivery? Fuel injector? Fuel injector harness, And compression on that cylinder?

No I have not. Was wanting to look into the injector but have not yet.

Visually I did look at the injector and last few inches of wires to that injector. Even moved the around while truck was running right and could not make it miss. That is all that I have done fuel wise so far.

Have you done this to the wires going to the coil on #5? Wiggle wires...

Yes, I did. Could not make it missup either.

Well checked the resistance on several fuel injectors and I'm getting 13.4 to 13.5 ohms on all except cylinder 5 I get 13.5 to 13.6. Sounds good to me. I'm leaning towards a clogged injector. But, I am going to buy a compression tester and check compression this weekend.

Almost feel like telling you to switch the injector to a different spot but that is tedious and you would have to watch rolling or squishing the O-rings. Not to mention getting to it.

Thought about that. But, do not want to pull the rail without having new O-rings on hand.

Did you ever figure out what was wrong with your 1500? I’m now having the exact same problem, exact same cylinder showing, 3 misfire codes. Running rough exactly the same way, when I get on it let’s say half way to the floor the check engine light flashes and it starts running rough. If I switch off the ignition and crank back up it purrs like a kitten again.

I know it has been awhile, but what was the fix for this truck?

Hey did anyone ever figure out what's going on with this? I'm sort of having the same issue I changed the spark plugs and the coil I also did a compression test and had good compression. I'm just wondering was it the injectors or something else?

Forgot about this. Tuned out to be a lifter. The cam was replaced and lifters for cylinder 5 replaced. Problem fixed. That was last November 2018. Now have 166000 miles and still running good. Cost was about $4500 at Jacksonville Beach Dodge.