It dont like to start up but when it dose it runs good

Check for vacuum leaks.
Do It Yourself Diagnosis and Repair

It sounds like your on the right track, the next step is to do a compression test to verify good rings in that particular cylinder.

Firing order is same for 5.0L or 5.7L

i would check for obd codes and see if it still is misfiring and what cylinder

Check your choke system first, fix any anomalies then if all OK check your carb systems including your air cleaner.
If those steps doesnot resolve your problem ask me again for other possibilities. Good luck

on carb is a screw buddy fiddle with tis screw till it runs i had this problem as well

Is it a two stroke machine , do you mix your own fuel.

If so over dosing on the oil component will cause your problem, check for the right mix levels and follow them.

Is the choke going full back to zero ?

Are you running the right type pf plug for that engine, some run hot some dont

Is the engine running smooth or lumpy.
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For a four stroke engine

Your engine may either be running very rich or there is wear on the bores causing oil to get to the electrode.

You can obtain a spark plug extender which takes the plug out of the direct line of fire

dont go changing bits ,then find it still doesnt work ??chances are they are right but take it to garage as an incorrect diagnosis will cost you money in the long run

Hi you should change the coolant temp sensor this is a white sensor on top of the intake and is part ot the computer system.

you have a fuel injector leaking
you need to pull your spark plugs and find the cyl that is different and that will be your bad fuel injector and alos replace your plugs
good luck
paul