How to Replace Spark Plugs on a 2016 Cadillac SRX (Front & Rear Bank Under Intake)
Step-by-step DIY guide with required tools/parts, intake manifold removal tips, and 11 ft-lb (15 Nm) torque spec for 2010, 2011
How to Replace Spark Plugs on a 2016 Cadillac SRX (Front & Rear Bank Under Intake)
Step-by-step DIY guide with required tools/parts, intake manifold removal tips, and 11 ft-lb (15 Nm) torque spec for 2010, 2011
🔧 SRX - Spark Plug Replacement
On your SRX, the front-bank spark plugs are straightforward, but the rear-bank plugs sit under the upper intake manifold. You’ll remove a few intake parts to reach all 6 plugs, then reinstall everything carefully to avoid vacuum leaks and misfires.
Difficulty Level: Intermediate | Estimated Time: 2.5-4.0 hours
⚠️ Safety & Precautions
- ⚠️ Work on a fully cool engine; the rear bank gets very hot.
- ⚠️ Disconnect the negative battery cable to prevent accidental shorts.
- ⚠️ Keep dirt out of the intake—cover openings with clean shop rags immediately.
- ⚠️ Do not use anti-seize on plated OEM-style plugs; it can cause over-tightening.
🔧 Required Tools
You'll need the following tools for this repair:
- Safety glasses
- Nitrile gloves
- 3/8" ratchet
- 3/8" torque wrench (10–30 ft-lbs range)
- 5/8" spark plug socket (rubber insert)
- 3/8" drive extension set (3", 6", 10")
- 3/8" universal joint
- 7mm socket
- 8mm socket
- 10mm socket
- 13mm socket
- Flat-blade screwdriver
- Trim clip removal tool
- Needle-nose pliers
- Compressed air blow gun
- Shop rags
- Paint marker
🔩 Required Parts
HowToo sells all the parts you need for this repair:
- Spark plugs (iridium, OEM-equivalent) - Qty: 6
- Upper intake manifold gasket set - Qty: 1
- Throttle body gasket - Qty: 1
- Dielectric grease - Qty: 1
📋 Before You Begin
- Park on level ground, shift to Park, and set the parking brake.
- Open the hood and let the engine cool completely.
- Use a 10mm socket to disconnect the negative battery cable and tuck it aside.
- Use a paint marker to mark any hoses/connectors you unplug so they go back to the same place. This prevents vacuum-leak mistakes.
🔨 Step-by-Step Instructions
Follow these steps in order:
Step 1: Remove the engine cover and intake duct
- Pull up to remove the engine cover (it’s held by push-on grommets).
- Use a 7mm socket (or flat-blade screwdriver) to loosen the air duct clamps.
- Unplug the MAF sensor connector (press the lock tab), then lift the duct out.
Step 2: Replace the front-bank spark plugs (easy side)
- Locate the front three ignition coils (each sits on top of a plug).
- Unplug each coil electrical connector (press tab, pull straight back).
- Use a 10mm socket to remove each coil bolt, then pull the coil straight up.
- Blow out the spark plug well using compressed air blow gun so debris can’t fall into the cylinder.
- Use a 5/8" spark plug socket with a 3/8" extension and ratchet to remove the spark plug.
- Install the new plug by hand first using the spark plug socket and extension (no ratchet) to avoid cross-threading.
- Use a torque wrench to tighten: Torque to 15 Nm (11 ft-lbs). (A torque wrench is a tool that tightens to an exact safe value.)
- Put a small amount of dielectric grease inside the coil boot, reinstall the coil, and tighten the coil bolt snugly with the 10mm socket.
Step 3: Remove components to access the rear-bank spark plugs
- Unplug the throttle body electrical connector and any sensors attached to the intake area (use the lock tabs; don’t yank wires).
- Use trim clip removal tool and needle-nose pliers as needed to release hose clips and retainers.
- Remove the throttle body from the intake using an 8mm socket (set it aside carefully).
- Disconnect the PCV/vacuum hoses and brake booster vacuum line from the upper intake manifold (twist gently to break the seal).
- Use a 10mm socket to remove the upper intake manifold bolts.
- Lift the upper intake manifold off and immediately cover the lower intake openings with shop rags.
- Tip: Take a quick photo before unplugging hoses.
Step 4: Replace the rear-bank spark plugs (under the manifold)
- Unplug the rear three ignition coil connectors.
- Use a 10mm socket to remove the coil bolts, then pull the coils straight up.
- Blow out each spark plug well using the compressed air blow gun.
- Use a 5/8" spark plug socket, extensions, and a universal joint to remove the plugs.
- Thread new plugs in by hand first, then tighten with a torque wrench: Torque to 15 Nm (11 ft-lbs).
- Apply a small amount of dielectric grease inside each coil boot and reinstall coils.
Step 5: Reinstall the upper intake manifold and throttle body
- Remove the shop rags from the intake ports.
- Install the new upper intake manifold gaskets (make sure they sit flat and fully in their grooves).
- Set the upper intake manifold back in place evenly (don’t pinch any wiring).
- Tighten the upper intake manifold bolts using a 10mm socket in an even crisscross pattern.
- Torque: Tighten to OEM specification using a torque wrench (spec varies by fastener set; use service data if available).
- Install the throttle body with a new throttle body gasket and tighten bolts with an 8mm socket.
- Torque: Tighten to OEM specification using a torque wrench.
- Reconnect all hoses and electrical connectors (use your markings/photos).
Step 6: Reinstall the intake duct and engine cover
- Reinstall the intake duct and tighten the clamps using a 7mm socket.
- Reconnect the MAF sensor connector.
- Press the engine cover back onto its grommets.
- Reconnect the negative battery cable using a 10mm socket.
✅ After Repair
- Start the engine and let it idle for 2–3 minutes.
- Listen for hissing (vacuum leak) and watch for a check engine light.
- If the idle is rough, shut it off and recheck coil connectors and vacuum hoses.
- Take a short test drive, then recheck for any loose clamps or fuel/vacuum smells.
💰 DIY vs Shop Cost
Shop Cost: $450-$850 (parts + labor)
DIY Cost: $70-$180 (parts only)
You Save: $280-$780 by doing it yourself!
Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 2.5-4.0 hours.
🎯 Ready to get started?
HowToo makes it easy: same-day/2-day shipping on every part, plus all the tools and specialty tools you need! Check out the parts and tools sections below to add everything to your cart.


















