How To Replace Spark Plugs 03-07 Cadillac CTS

Difficulty: Advanced · About 50 min · Cadillac Cts

Replace the spark plugs, including lifting the intake manifold, on a 2003-2007 Cadillac CTS.

Steps

1. Loosen the intake manifold

   Remove the oil fill cap and engine cover, remove the manifold's top 13mm bolts, loosen the air intake hose clamp and pull the box off, loosen the stud with a 10mm wrench, then loosen the 18mm bolt to pull the bracket back from the hose.

2. Remove an ignition coil

   Loosen its 10mm bolt, pry off its sensor harness, lift the intake manifold for clearance, then remove the coil.

3. Remove the old spark plug

   Slide a spark plug extension onto it, then remove it.

4. Install the new spark plug

   Gap it to .043, insert it into the socket, feed it into place, tighten it, then torque it to about 17 ft-lb and repeat for the other side.

5. Reinstall the ignition coil

   Insert it into place, connect its sensor harness, then tighten its 10mm bolt.

6. Tighten the intake manifold

   Snug its 13mm bolts preliminarily then torque them to about 20 ft-lb, tighten the stud and the 18mm bolt, press the intake box back on and tighten its hose clamp, then refit the engine cover and oil cap.

Check your vehicle’s repair manual for exact specifications and fit.