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Old 03-17-2016, 09:13 PM
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trackers
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Default engine miss fire

I have a 2006 4.6 with a vortech sc, 455 rwhp. put it away for winter, ran great, started it this spring and skips. codes show multiple miss fire and # 4 cyl. is dead, 22,000 miles, pulled plug, looks good, put plug in coil, seems to have good fire, listened to injector, and hear it click, any idea's????????????
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Old 03-17-2016, 09:24 PM
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How's the fuel and fuel filter? If it's still the same it needs to be dumped and replaced.

It could be several things. Vaccum leaks week do that, poorly charged batteries can but it's rare, bad alternator.

The easiest thing to do is empty the fuel to nothing, replace with good fuel and some Seafoam.

Then check plugs, make sure coils are connected, check the oil etc.
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Old 03-18-2016, 06:17 AM
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I filled the tank before I stored it with 93 octane, only had 22,000 miles on car, don't mind dumping the fuel and changing the filter, but will I have to do this every winter? and if so, is there an easy way to drain the full tank?
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Old 03-18-2016, 10:23 AM
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next time, add appropriate amount of sta-bil (I think that's how its spelled) to the fuel prior to storage, or make sure its empty. youll have to siphon it out, I don't think the tank has a drain valve on it. good luck
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Old 03-18-2016, 10:52 AM
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Fuel filters are cheap. So is gas. Always store vehicle with minimal fuel. It only lasts a month or two if it's fresh and depending on what additives are in it.

Stabil does not work very well. Use Seafoam.

On the fuel rail there is a disconnect on the driver side. A$5 tool is required to disconnect it. Go to any auto parts store and show them what you want to disconnect. They should have one on the shelf.

Get a fuel line (probably 1/2") to connect to three line you disconnect from your car. Just turn on the key and the fuel pump will turn on and pump out the fuel.

Replace with fresh fuel and some seafoam. I would let the car idle with the seafoam in the tank until it gets to operating temperature. If it runs better you're good. If not, odd let it sit again until the following day and let the Seafoam dissolve anything it can.

Put battery on a charger while it's in there. Unless it's been on one.

Best of luck!
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Old 03-18-2016, 01:45 PM
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thank you, i'll be trying that this weekend
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Old 03-18-2016, 03:43 PM
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you will most likely have to cycle the key to keep the pump running as it will only pump for 5 sec or so until the engine is started. but since you have #4 dead and have good spark there i would suspect either a plugged injector/ fuel rail. i have seen several stored cars end up with rust and gunk due to ethanol fuel. it would be a good idea to pull the fuel rail and pull the injectors to inspect
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Old 03-30-2016, 08:47 PM
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well I dumped the fuel, added sea foam, let sit for 24 hours, no change, changed coils, no change pulled plug, hooked it to coil, fires, but weak white spark bought new plug, cyl. came to life. cleaned 2 other plugs that show miss fire, all came to life, then checked with the speed shop that built this car and they suggested going to autolite hto racing plugs. 2 stage colder because of my 10 lb boost with vortech. so I got them coming. just wanted to thank you all for help and sharing this with you
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Old 03-30-2016, 08:58 PM
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at least that was a cheap fix, glad to hear it. i prefer NGK TR6 plugs for what its worth
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Old 03-31-2016, 02:01 AM
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Originally Posted by trackers View Post
cleaned 2 other plugs that show miss fire
Did any plugs show Mr. Fire?
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