How many spark plugs are there on the 1994 Ford E2 50 it's a 5.8 L V8

There are indeed 8 spark plugs for the V8 engine in this vehicle, if it is for a 5.8L V8 engine. I cannot explain how there could be 10 wires. 8 would go to the various cylinders, and 1 would go to the coil.

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you have a 1994 E250 5.8 L (V8) engine,and it does have 8 cylinders,one plug for each cylinder. I have one,only my 5.8L 351 engine is in an F150 Pick-up. you have just overlooked one plug..also,count the wires on the distributor cap again,as stated from DaveJM,you should have 9 total with the wire in the center of the cap going to the ignition coil.follow the wire that hasn't been taken off the plug yet,and you'll see that last plug.use only Motorcraft Plugs,gap at .044