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rough idle and rich need help

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Old Apr 4, 2013 | 04:49 PM
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From: Machinegun Valley KS
Default rough idle and rich need help

Well today started shitty fist codes were pending random missfire and mass air flow then startes driving to work then cylinder 4 p0304 code with ses flashing. So I changed plug out same problem swapped wires and coil packs went away. Then just plain random missfire after all new plugs plus running rich can smell raw fuel through exhaust. Called tuner and heshesaid to boil injectors I do t think that be problem. I cleaned maff and still rough idle not as bad but still is pig rich and ideas fellas im at work trying to get figueed out wont be able to do anything with injectors dont have the fuel disconnect lines. Help appriciated. Need truck running right have to make 200 mile trip monday
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Old Apr 5, 2013 | 10:05 AM
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From: warwick,ny
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I would say it's the bad coil or wire from cylinder #4.
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Old Apr 5, 2013 | 10:19 AM
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A leaking header gasket will also cause those symptoms. How long has it been since you have replaced all the plug wires?
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Old Apr 5, 2013 | 12:16 PM
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Just replaced all plugs wires about year old waitn on coil pack. On the drive home it set code for cylinder 2. So will find out here shortly if thats the case hopn its coil pack due to fact ive got spares
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Old Apr 5, 2013 | 01:39 PM
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I've had bad luck with run of the mill wires until I went with MSD. Check the resistance of the plug wires before putting them on.
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Old Apr 5, 2013 | 04:54 PM
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Well heres the update now replace all 4 coils on passenger side with my spares no code better idle runs smoother. I wil have to replace header gasket I did see where its leakn shoulda used the stockers owell. It just keeps throwing pending code for cylinder 2 so ill replace gasket and see if she goes away
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Old Apr 7, 2013 | 01:48 PM
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Alrite got everything fixed was bad coil pack burnt out exhaust manifold gasket as well and one stuck injector

Dont trust gaskets that come with headers
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Old Apr 7, 2013 | 01:56 PM
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Is that another paper gasket?

Make sure to use the MLS style.
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Old Apr 7, 2013 | 02:04 PM
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From: Machinegun Valley KS
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Wish I still had my mls gaskets looked all over for them I know I saved them. Had to go get sone orielly specials till I can go and get the mls ones
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