1997 Crown Vic with a miss.

My Crown Vic recently developed a miss on the #4 cylinder.I have changed the plugs,and wires.It still has the miss.I checked the coil pack and the Fuel Injector and both are good.The check engine light is
steady from idle up to about 40mph.Above 40mph and the light blinks.Any ideas what the cause might be?
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Check your fuel pressure in the rail, also.
A compression test may be of some help to you, too. It may be that you have a sticky valve or a leaky piston ring, or even worse, a blown head gasket. Try having the vehicle scanned at an Autozone or local shop for a code reading and tell us what the code is. Im assuming youll get a P0304 which is a Cylinder 4 Misfire. Ah, and the blinking MIL lamp indicates that there is a misfire that is capable of damaging your catalytic converter. Dumping raw fuel into the catalyst is not so much a good thing :P
"bob_in_stpete" wrote: > My Crown Vic recently developed a miss on the #4 cylinder.I > have > changed the plugs,and wires.It still has the miss.I checked > the coil > pack and the Fuel Injector and both are good.The check engine > light is > steady from idle up to about 40mph.Above 40mph and the light > blinks.Any ideas what the cause might be?
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Ok so I did a compression test today and I am getting zero compression on the number 4 cylinder.Will be removing the valve cover this week to check what the cause is.Thanks for the help.

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