Sounding Like My Dad

My Dad is an old school gearhead. He grew up getting his hands dirty repairing everything GM and Chrysler produced from 1950's to the late 1980's. At that point the overall mechanics at automobiles changed significantly as new sensors added to the layers of hoses, wiring, and pipes that were already in place. One of his favorite rants now is how complex cars have gotten.

"If it's something more than changing a belt or a hose or the oil you have to be a fricken' scientist," he would commonly gripe while sucking back a cold one.

My perspective was that these advances helped mechnanics find out what was wrong with your car faster and improved the driving experience for consumers. That was until I needed to change the spark plugs on my Jeep.

The last time I needed to do this I was driving a different vehicle and the process was pretty simple.
1. Gently deattach the spark plug wire from the plug.
2. Remover the spark plug from the engine block.
3. Insert new spark plug.
4. Replace spark plug wire.

I was expecting much of the same until I did a quick search for some basic instructions. This is what I found:

Removing plugs - 3.7L engine

Each individual spark plug is located under each ignition coil. Each individual ignition coil must be removed to gain access to each spark plug. The coil fits into machined holes in the cylinder head. A mounting stud/nut secures each coil to the top of the intake manifold. The bottom of the coil is equipped with a rubber boot to seal the spark plug to the coil. Inside each rubber boot is a spring. The spring is used for a mechanical contact between the coil and the top of the spark plug. These rubber boots and springs are a permanent part of the coil and are not serviced separately. An o-ring is used to seal the coil at the opening into the cylinder head.

1. Remove necessary air filter tubing at throttle body.

2. Prior to removing ignition coil, spray compressed air around coil base at cylinder head.

3. Depending on which coil is being removed, the throttle body air intake tube or intake box may need to be removed to gain access to coil.

4. Disconnect electrical connector from coil by pushing downward on release lock on top of connector and pull connector from coil.

5. Clean area at base of coil with compressed air before removal.

6. Remove coil mounting nut from mounting stud.

7. Carefully pull up coil from cylinder head opening with a slight twisting action.

8. Remove coil from vehicle.

9. Prior to removing spark plug, spray compressed air into cylinder head opening. This will help prevent foreign material from entering combustion chamber.

10. Remove spark plug from cylinder head using a quality socket with a rubber or foam insert. Also check condition of ignition coil o-ring and replace as necessary.

Installing plugs - 3.7L engine

Special care should be taken when installing spark plugs into the cylinder head spark plug wells. Be sure the plugs do not drop into the plug wells as electrodes can be damaged.

Always tighten spark plugs to the specified torque. Over tightening can cause distortion resulting in a change in the spark plug gap or a cracked porcelain insulator.

1. Start the spark plug into the cylinder head by hand to avoid cross threading.

2. Tighten spark plugs to 20 Ft. lbs. torque.

3. Before installing ignition coil(s), check condition of coil o-ring and replace as necessary. To aid in coil installation, apply silicone to coil o-ring.

4. Using compressed air, blow out any dirt or contaminants from around top of spark plug.

5. Position ignition coil into cylinder head opening and push onto spark plug. Do this while guiding coil base over mounting stud.

6. Install coil mounting stud nut.

7. Connect electrical connector to coil by snapping into position.

8. If necessary, install throttle body air tube.

All this to replace spark plugs? My Dad was right, cars are getting way to complex.