How do I find and change the spark plugs

If you are saying everything is ok when the engine first starts but number one starts to miss when at operating temp. Sounds like the number one coil has developed a internal crack that opens up when hot or at operating temp..causing a miss.change it.but before changing the coil check the spark plug wire it may be breaking down when hot..good luck

try changing the spark plugs

cylinder 1 getting too hot causing ceremic crack could have wrong heat range plug in which spark plug too hot.or need replace spark plug wires.one plug wire could be bad best replace all spark plug wires.

If you have a 4.2 L engine, Remove the 10mm bolts on the coils, on top of the engine, remove the electrical connector then the coil, your truck has individual coils, spark plugs are in the hole, 5/8 spark plug socket, don't buy cheap spark pluggs for this truck, it will miss fire, I prefer autolites Autolite Xp Iridium/Spark Plug

Hi,
Looks like some engine oil goes into the cylinder and contaminate your spark plug, thus making your plugs miss.
Look where that oil damp spark plug located at cylinder number, in that cylinder the valve seal is to be replace immediately. Valve seal is located on top of the engine that seals the intake/exhaust valve and valve guide, from oil going in the cylinder.
You could ask your mechanic to do the job, it is a bit hard to replace it. the parts needed coat just under $5.
Hope that helps you out!
Thanks for using Fixya!

1. When idle, listen to the engine and see if there is any miss fire. If you hear some misses, not a smooth run, it means either you have to replace the spark plugs because one or more are not working or one of the leads to the spark plugs isn't connecting properly. It is recommended you change the spark plugs every 10.000 miles given it's a 15 years old car.
2. If there's a smooth idle run, then there might be something wrong with the fuel pump (which is located close to the fuel tank under the car) or with the air valve which is located near the engine, both can be clogged not passing enough fuel or air required.

could just need a tune up,you could also pull of the distributor cap and look for oil intrusion, if there is you will need to replace the distributor

missing would show itself at low engine speeds.bad starting.or heavy load (going up steep hills)a miss at high speed would not be felt (normally)without other symptoms(lack of power etc)have you tried using higher octane fuel......mazda rec 92+ octane...

OR MAYBE YOUR GAS FILTER LOCATED UNDER YOUR OIL FILTER, PANEL UNBOLTS UNDER RIGHT FENDER WELD FOR EASY ACCESS, THE BIGGEST FIX FOR ME WAS TO TAKE OFF THE ADVANCE AUTO BRAND NEW SPARK PLUG WIRES AND INSTALL NAPA WIRES, DISTRIBUTER, ROTAR BUTTON, AND NGK ORIGINAL SPARK PLUGS. ROB

it sounds right, it is called a light load miss. it occurs mostly at 45-50 mph on slight incline and it feels like a bucking or hesitation. It commonly ocurs when there is carbon tracking on a spark plug porcelin (sp) . note . if the porcelin has carbon tracking so does the plug wire boot. the spark will travel through the carbon track in teh boot after plug replacement causing premature failure of the plug. it is a good idea to replace plugs and wires if this is the cause of your miss.