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P0301 After Cylinder Head Replacemant

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Old 06-28-2013, 10:16 AM
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Default P0301 After Cylinder Head Replacemant

I just replaced my head with a Clearwater Cylinder Head and now I have a misfire on Cyl. 1. I discovered the cracked head early, never overheated and oil pressure is good. Injector is pulsing, but the new spark plug was never fired. Replaced spark plug with one from the old head and it is still missing. Would the coil rail only stop working on one cylinder or would the whole thing go out?
Old 06-28-2013, 10:44 AM
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Originally Posted by HiPoint
I just replaced my head with a Clearwater Cylinder Head and now I have a misfire on Cyl. 1. I discovered the cracked head early, never overheated and oil pressure is good. Injector is pulsing, but the new spark plug was never fired. Replaced spark plug with one from the old head and it is still missing. Would the coil rail only stop working on one cylinder or would the whole thing go out?
Just cylinders 1 and 6. If cylinder 1 plug only is not firing and 6 is okay, then the problem is isolated to between the coil and the #1 plug.
Old 06-28-2013, 10:50 AM
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Substitute a known good plug wire and see what happens.
Old 06-28-2013, 10:50 AM
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CCKen: Are you saying I could have a bad coil?

Last edited by HiPoint; 06-28-2013 at 10:53 AM. Reason: needed to specify who I was talking to.
Old 06-28-2013, 11:11 AM
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Originally Posted by HiPoint
CCKen: Are you saying I could have a bad coil?
No. One coil fires two cylinders at the same time. One cylinder being fired is the power stroke for that cylinder, the other cylinder (plug) being fired is on its exhaust stroke and is called a 'waste spark'.

You're looking at cylinder number 1 as having a problem. If the coil that fires 1 & 6 is bad, number 6 would be bad as well.

Do like Firestorm500 recommends and substitute a known good plug wire and see what happens. Also, pull number 6 plug and see if it has been firing clean.

Push comes to shove, swap number 1 injector to the number 2 position and see if the problem follows.
Old 06-28-2013, 11:27 AM
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Alright. No plug wires to swap, this is coil rail directly on plugs. It's just weird that the Cylinder 1 plug was light brown and wet like it had never fired and Cylinder 6 looked like it had fired. Cylinder 1 injector is pulsing, verified it had power and can hear it with stethoscope.
Old 06-28-2013, 12:32 PM
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Originally Posted by HiPoint
Alright. No plug wires to swap, this is coil rail directly on plugs. It's just weird that the Cylinder 1 plug was light brown and wet like it had never fired and Cylinder 6 looked like it had fired. Cylinder 1 injector is pulsing, verified it had power and can hear it with stethoscope.
If number one plug is light brown but wet it may mean it was firing but was wet with fuel so there was incomplete firing.

Just because an injector is 'clicking' it doesn't mean it is atomizing properly. The pintle may be stuck open and the solenoid in the injector is operating but not closing the pintle.

Like mentioned, swap number 1 injector with number 2 and see if the problem follows.

As far as the coil pack 'wire' goes, verify the clip inside the boot is okay. Make sure the clips in the boots aren't all packed with dielectric grease.
Old 06-28-2013, 12:53 PM
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Thanks, I appreciate the help. I work 2nd shift, will get back at it tomorrow morning.
Old 06-28-2013, 01:26 PM
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#1 plug might be bad. Put a known good plug in #1 or swap a couple around and see if the lack of firing follows the former #1 plug.
Old 06-28-2013, 02:03 PM
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Originally Posted by Firestorm500
#1 plug might be bad. Put a known good plug in #1 or swap a couple around and see if the lack of firing follows the former #1 plug.
I've swapped the plug with a known good one and it's still P0301.
Old 06-30-2013, 12:02 PM
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So I've swapped injectors 1 and 2 and still P0301. Swapped coil rail with known good coil rail just for the hell of it and still P0301. Any other suggestions?
Old 06-30-2013, 02:56 PM
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Cyl 1 compression test?
Old 07-01-2013, 07:40 AM
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Did the Clearwater head come complete, i.e, with valves, valve stem seals, and springs?

Did you keep your old rockers, pivots, and bridgesor did you install new?

Was the wetness on #1 plug oil or fuel?
Old 07-01-2013, 09:37 AM
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^Yes, the Clearwater head came complete. I used my old lifters, pushrods and rocker arms. Wetness on the plug was fuel. Haven't tested compression yet but that's what I'm leaning towards. Going to pull the valve cover first and check pushrods, lifters and springs right now.
Old 07-01-2013, 10:00 AM
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Originally Posted by HiPoint
^Yes, the Clearwater head came complete. I used my old lifters, pushrods and rocker arms. Wetness on the plug was fuel. Haven't tested compression yet but that's what I'm leaning towards. Going to pull the valve cover first and check pushrods, lifters and springs right now.
Sometimes when the rocker bridges are installed they get twisted, throwing the rocker off center to the valve stem. If you are going as far as checking all those items make sure they aren't twisted.

Rocker arm cap screws should be torqued down (21 ft./lbs.) when the respective cylinder is at TDC compression to avoid uneven torquing.


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