Gonna need to know which engine you have in there.
1-6-5-4-3-2 Clockwise on distributor cap.
They have to be in the firing order.
Is there a picture of distributor cap firing order for 2003 ford f150 4.2 engine
Which engine.
It depends on the firing order of the engine
get a book Run your spark plug wire from the #1 plug to the #1 lug on the distributor cap. Then follow the rest of the firing order going clockwise around the cap.
are the plug wires in the correct sequence for firing order? Are the coil wires all connected? Did you remove the distributor and possibly put it out of time?
firing order from spark plug to the distributor cap
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1,3,7,5,8,9,10
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