cyl 5 miss

jawa · 05-02-2011, 03:22 PM

I'm getting a missfire on cyl 5 under moderate to heavy loads. Wires are new. Any thoughts

Shiwnath · 05-02-2011, 03:27 PM

Good place to start: http://www.obd-codes.com/p0305

C.CLARK33 · 05-02-2011, 03:54 PM

Just had the same thing happen to my 03 3.4 on mine it was the coil.

jawa · 05-02-2011, 04:12 PM

Damm coils. Lol

jawa · 05-02-2011, 04:17 PM

was yours starting weird too clark?

C.CLARK33 · 05-02-2011, 04:39 PM

Quote:

Originally Posted by jawa

was yours starting weird too clark?

Not too bad but i could tell it more when i would give it the gas between 45 and about 65 like when i tried to pass somebody.

jawa · 05-02-2011, 04:45 PM

I can feel it when i hammer it hard , feels like its down on power

TheEdgeofSanity · 05-02-2011, 11:48 PM

yeah, mine was doing the same thing.... according to my mechanic, it was the coil going bad and over time the plug fouled out and made it get worse

Redog · 05-03-2011, 12:33 AM

mine would do that, but it was the battery grounding out on my intake pipe

sleepyalero · 05-03-2011, 12:59 AM

Quote:

Originally Posted by Redog

mine would do that, but it was the battery grounding out on my intake pipe

so how'd you fix that?

TurboAleroGT40 · 05-03-2011, 01:29 AM

So question if the coil is going bad, shouldn't you get misfire also on cyl 2? Because 5 and 2 are on the same coil.

a.graham52 · 05-03-2011, 07:22 AM

Quote:

Originally Posted by TurboAleroGT40

So question if the coil is going bad, shouldn't you get misfire also on cyl 2? Because 5 and 2 are on the same coil.

thats what i would think too. also check your spark plug to make sure its not cracked and/or carbon tracking.

C.CLARK33 · 05-03-2011, 04:42 PM

In the coil on plug system, each spark plug will have its own individual coil that sits right on top of it. This is a so called Direct Ignition module.
In a waste spark system, the two spark plugs will share the same coil. So therefore, in this system both spark plugs are attached to the coil and they are fired simultaneously. While one cylinder is toward the end of its compression stroke, its piston pair is nearing the end of the exhaust stroke, and both plugs are then fired.

Even though the spark plugs are manufactured exactly the same, if they are re-installed after there has been some extended use, they should then go back into the cylinder from which they came from. The reason for this is because the electrons will align themselves favorably with one direction of current flow. While the one plug will receive positive potential (voltage) at the wire side, the piston pair will receive the negative potential. The negative potential is what causes the second plug to fire instead of the voltage just going straight to ground after firing the first one. Vehicles seem to use the conventional theory as opposed to the electron theory of current flow.

The waste spark system is better than having a single coil, and it is cheaper than having a coil on plug. The disruptive discharge tesla coil is an earlier coil of the ignition coil in the ignition system. It also used the same principles of the ignition coil that is used in today’s vehicles.

xXManwhoreXx · 05-05-2011, 08:07 AM

When you get on it the coil heats up the heat causes it to expand to the point where it loses contact. It cools after you let off and its fine again... You need a new coil pack

jawa · 05-05-2011, 01:52 PM

wut is carbon tracking?

a.graham52 · 05-05-2011, 03:04 PM

its where the spark finds an alternative path to ground such as cracked porcalin. it will show up as a black line on the plug.