Changing Sparkplugs

Our plugs last a long time, 60,000 miles for platinum or 100,000 for iridium, but some day you will need to change them or maybe you just want to check them to see how your engine is doing. Either way you've got to get to them. This is the procedure on the turbo. You can also find the instructions in the TSRM for the Turbo and NA. While you are here I suggest doing a compression test since the extra work involved is basically zero, and it could alert you early to the condition of your engine.

Tools:	Ratchet	8" extension
	10mm Socket	U-Joint
	12mm Socket	Torque Wrench
	12mm Long Socket
	16mm Long Socket

Materials:	Anti-Seize goo
	6 Spark Plugs

While you are here

1.	Compression Test
2.	Check and/or replace plug wires

Teardown

1.	Remove the two 10mm bolts holding down the ISC pipe and the remove it by disconnecting the two vacuum hoses and large black hose on either side.
2.	Remove the 5 10mm nuts holding down the ignition pack cover and remove the oil cap. Now carefully remove the ignition pack cover and then replace the oil cap.
3.	Using a 12mm long socket remove the 3 nuts holding the throttle body linkage assembly to the exhaust side of the head. Remove the throttle body linkage arm and remove the 12mm bolt holding the throttle body linkage assembly to the center valley. Now you can maneuver this out of your way when you need to.
4.	Disconnect the ignition pack connector, the 6 spark plug wires and using a 12mm wrench remove the bolt holding the grounding wire to the intake valve cover. Now remove the ignition pack from the car.
5.	Carefully remove the 6 sparkplug wires.
6.	If you have compressed air now is a good time to blow out the spark plug wells to get the crud and oil out before you remove the plugs.
7.	Using a 16mm long socket and an extension remove the 6 plugs. Plug #4 will be difficult because the PCV pipe is in the way. so attach your universal joint to that socket then you extension to that and it should work fine. When you take the plugs out keep them in numbered order.

Reading your old plugs:
Before you put in your new plugs you should "read" your old plugs to get a good idea of how the engine is running. They can tell you a lot about what goes on inside of a cylinder. You can use the article on sparkplug condition to help you translate what they are saying. It is also good that they are all similar looking. This shows that all cylinders are about the same. I won't go into any diagnostics here cus it would be lengthy with all the permutations.

Gapping The Plugs:
When gapping the take care not to damage the center electrode. On Iridium they say don't ever touch it which makes it difficult to gap. For the others bend the grounding electrode with the gapping tool just a bit and then recheck. The TSRM lists the proper gap. For your info, if the gap is excessively wide the spark can get blown out, if it is too small the spark kernel lighting the gas doesn't give as much ooomph as it could.

Reassembly

1.	Clean the wires, plug threads and try to sop up any extra oil in the plug valley before starting.
2.	I recommend putting anti seize on the plug threads. I had a plug strip out of a dead cold block once, luckily it was an extra head that I was taking apart. This $0.99 item could save you loads of hassle.
3.	Reinstall the spark plugs, after verifying the air gap, torqueing them to 13 ft/lb with the 16mm long socket.
4.	Replace the plug wires.
5.	Replace the ignition pack connect the 6 plug wires, connect the electrical connection, bolt the 12mm grounding wire to the head, and tighten the 10mm bolt.
6.	Replace the throttle body linkage, tighten the 3 bolts to the exhaust side of the head, and tighten the bolt to the center valley gasket.
7.	Replace the ignition pack cover and tighten the 5 nuts.
8.	Replace the ISC pipe, reconnect the hoses to both sides, and tighten the 2 10mm bolts that hold it to the 3000 pipe.
9.	Fire it up, hope it all works :).

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