P0301 After Cylinder Head Replacemant
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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?
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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?
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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.
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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.
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.
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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.
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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.
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.
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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?
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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?
Did you keep your old rockers, pivots, and bridgesor did you install new?
Was the wetness on #1 plug oil or fuel?
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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.
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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.
Rocker arm cap screws should be torqued down (21 ft./lbs.) when the respective cylinder is at TDC compression to avoid uneven torquing.