dodge durango random misfire

[pbatemon]

okay I’m pretty much lost as to what this is, I have an 98 dodge Durango with the 5.2 anyways I keep getting this misfire code and its for #1 and #5 then after clearing the code i drove it and got a misfire in #2 and #8 I’ve changed the spark plugs, the plug wires, rotor and rotor cap and all that good stuff, but still no change, it also dose this strange thing around 45mph and up where it’s jerking, as if someone’s putting it outta gear and back in, this stops when I step on the gas hard and it downshifts, this is also when the light comes back on is when it’s jerking, and there’s even some times the check engine light just turns off and the codes arnt to be found, I have no idea what’s going on, i even attempted a compression test #1 80 #2 125 #3 95 #4 80 #5 90 #6 100 #7 105 #8 90
i think the one that makes me wonder is #2, anyway shoot me any ideas you got, any help would be greatly appreciated, thanks

Topic

[LJ11194]

Check my edit.

[LJ11194]

How much of an effect does temperature have on the ohm reading? Because according to my test, my coil is well within spec. However, it is only 30*F. It’s also not going to come off without tools I lack because whoever tried replacing it last stripped out the heads of the screws holding it on. (The manual says those are supposed to be 10mm bolts btw)

I’m heading to the U-pull-it Wednesday to get another one regardless, because I have nothing else to try right now and it should be cheap enough to be worth a try.

[EricTheCarGuy]

Forget about ohming out the coils. I’ve even talked to engineers about this and there really is no way to tell if a coil is bad by checking it’s resistance. I take that back, you can tell if it’s completely dead but you can’t tell if it’s failing under load. That said, lets back the truck up.

Start with a power balance test to see if you can nail down the cylinder(s) that are effected.

If you find one or more cylinders that are down on power then you need to find out why. This could be due to spark, fuel, or a mechanical issue. You can start by pulling the plugs and looking at them. If the plugs on the bad cylinders look different than the rest this could indicate a fuel delivery or vacuum leak problem. You could also do a compression test. This is a good guide for that.

With that many miles it’s very possible you have worn engine internals that could cause a miss.

Diagnosis is a scientific process. Avoid jumping to conclusions and start with the simple stuff first.

Solving Performance Problems 1

Solving Performance Problems 2

Re Performance Problems

[pbatemon]

Thanks, checked with a scan tool today because the light was back on, and it came back with a 5 and 8, and some code ive never seen before, it said “manufacturer controlled fuel and air metering” checked the spark plugs and they all looked the same, a tiny bit of white but normal (at lest in my opinion) and i changed out the coil, no change at all, i will try a power balance tomorrow and see what happens, thanks for you help!

[EricTheCarGuy]

You’re welcome. Keep us posted.

[clay rutledge]

just wondering.. could this be a mechanical issue????stcky lifter or something..A mechanical issue will cause codes.but it’s just a thought

[college man]

do a compression test to rule out the mechanical issue.
most misfires are usually ignition or fuel related.

[Russell A Hawkins]

Make sure you have it at full throttle when checking compression

[Russell A Hawkins]

I also have a 5.9 intermident miss on #6 under load, it drinks coolant so I know there is an issue, when I got the vehicle it missed at idle pretty bad when hot so I decided to make it so it wouldn’t build psi in the system by removing the psi seal on the rad cap and it completely fixed the miss at idle so I’m thinking bad head and there is also some oil in the plenum which I’m not surprised since it has 235k, the confusion I’m having is it will run great all threw the pedal for a few days or so then all of a sudden it will slowly start to miss and then keeps getting worse and there’s been times where it’s running like ass and come to a stop and it’s running fine, all wires, cap etc are fine haven’t checked fuel psi yet, it doesn’t ping, no lifter ticks, it’s more than likely the coolant issue but the in consistency is baffling.

[Author]

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