Best place to start would be with spark plug and have a look at it. Wet with fuel would indicate no spark, carbon build up, bad wire or plug etc. If your familiar with testing at spark plug to confirm spark getting to plug, then do that first. If no spark to plug, coil pack would be next, or distributor parts such as cap, wires, rotor etc. If getting spark, then try cleaning and checking connections to injector. There are other more expensive things that may be causing it, but lets try the cheapest, most common and easiest first to narrow it down, and get back to me/us, if still having problem.
NEEDS A SPARK PLUG,OR COIL PACK ,OR POSSIBLY AN IJECTOR IT WILL BE ONE OF THE THREE IF THE COIL PACK IS PLUGGGED UP
Frist of all do you have a cylinder that is caplble of firing check compression the very frist thing to check if good check plug for cracks bad electro or fouled out it is poosible to have a bad coil or injector but mor likly to be a vacuum leak affecting that cylinder check all hose and intake runner to that cylinder
SOURCE: engine code p0307 cylinder #7 misfire
It could be carbon deposits on valve seats keeping valves from totally closing. You can try getting you a can of motorcraft PM3 top end engine cleaner and get engine up to operating temp then remove one of the small vacuum lines from the intake and draw the contents of the can slowly into the engine.After you have drawn in the contents shut engine off and let it soak for about 45 minutes then crank it back up and let it run until it clears. Now it will smoke like a forrest fire while you are doing this so don't be alarmed,just tell the neighbors you are spraying for mosqitos.This may cure the problem. If not you may be looking at a valve job.
This can be verified with a compression test if this is what is causing it.
SOURCE: 1996 ford f150 truck engine light on
What year is the truck ? if its a 1998 im sure its never had a tune up i would start with replacing the spark plugs and there is a very good chance that a coil is also bad
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DTC P0301 Cylinder 1 Misfire Detected
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DTC P0302 Cylinder 2 Misfire Detected
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DTC P0303 Cylinder 3 Misfire Detected
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DTC P0304 Cylinder 4 Misfire Detected
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DTC P0305 Cylinder 5 Misfire Detected
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DTC P0306 Cylinder 6 Misfire Detected
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DTC P0307 Cylinder 7 Misfire Detected
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DTC P0308 Cylinder 8 Misfire Detected
2004 Marauder and 2003-2004 Mustang vehicles built before 12/19/2004 equipped with 4.6L 4V/5.4 4V engine may exhibit a runs rough, lacks power, and engine misfire, prompted by a MIL light and DTC codes P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, and P0316.
ACTION
Diagnose engine for engine misfire concern. If diagnostics determine an engine misfire which is characterized by leakage through exhaust valve(s), only replace the affected cylinder head(s).
SERVICE PROCEDURE FOR VEHICLES WITH RUNS ROUGH/MISFIRE CONDITION:
1. Perform relative compression check on all cylinders. If abnormal, check cylinder leakage and actual compression for "low" cylinders refer to Workshop Manual (WSM), Section 303-00.
2. If leakage/compression check indicates a valve train concern, per valve train diagnostics in WSM, Section 303-00, replace cylinder head and cam assembly, pipe plugs and timing chain tensioner, per procedure outlined in WSM, Section 303-01.
3. If cylinder leakage and compression tests are inconclusive, perform misfire diagnostic, per TSB 05-22-8.
P0300?? Multiple Cylinder Misfire
P0301?? Cylinder #1 Misfire
P0307?? Cylinder #7 Misfire
are the codes start with the basics inspect plugs wires cap rotor and if all checks out do a compression test
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