How to Replace Ignition Coils on a 2016 Cadillac SRX (Fix Misfire & Rough Idle)
Step-by-step coil-on-plug replacement with tools, parts list, safety tips, and 89 in-lb (10 N·m) torque spec for 2007, 2008, 2009, 2012, 2013, 2014, 2015, 2016
How to Replace Ignition Coils on a 2016 Cadillac SRX (Fix Misfire & Rough Idle)
Step-by-step coil-on-plug replacement with tools, parts list, safety tips, and 89 in-lb (10 N·m) torque spec for 2007, 2008, 2009, 2012, 2013, 2014, 2015, 2016
🔧 SRX - Ignition Coil Replacement
Your SRX uses coil-on-plug ignition coils (one coil per cylinder). Replacing a bad coil fixes misfires, rough idle, and flashing check-engine lights by restoring strong spark to the spark plug.
Difficulty Level: Intermediate | Estimated Time: 1.0-2.5 hours (rear bank is tighter)
⚠️ Safety & Precautions
- ⚠️ Work on a cool engine to avoid burns.
- ⚠️ Keep fingers/tools away from the radiator fans; they can turn on unexpectedly.
- ⚠️ Disconnect the negative battery cable if you’ll be unplugging multiple connectors (recommended).
- ⚠️ Don’t pull on wiring; always release the connector lock first.
🔧 Required Tools
You'll need the following tools for this repair:
- Safety glasses
- Nitrile gloves
- Socket set with ratchet (1/4")
- 10mm socket
- 8mm socket
- 6" socket extension (1/4")
- Universal joint swivel (1/4")
- Torque wrench (in-lb)
- Flathead screwdriver
- Trim/panel removal tool
- Small pick tool
- Flashlight
🔩 Required Parts
HowToo sells all the parts you need for this repair:
- Ignition coil - Qty: 1-6 (replace only failed coil, or all six)
- Dielectric grease - Qty: 1
- Ignition coil boot (if separate from coil) - Qty: 1-6
📋 Before You Begin
- Park on level ground, shift to Park, and set the parking brake.
- Open the hood and let the engine cool fully.
- If disconnecting the battery: use a 10mm socket to remove the negative terminal and isolate it so it can’t spring back.
- Tip: Take a quick photo of each connector first.
🔨 Step-by-Step Instructions
Follow these steps in order:
Assumption: Stock intake/engine cover; rear-bank coils are accessible with extensions and a swivel.
Step 1: Remove the engine cover
- Grab the plastic engine cover and pull upward firmly to release it from the rubber grommets.
- If a corner feels stuck, use a trim/panel removal tool to gently pry up.
Step 2: Remove the air intake duct (to improve access)
- Use an 8mm socket (or flathead screwdriver, depending on clamp style) to loosen the hose clamps on the intake duct.
- Unclip/unplug any small resonator tube or sensor connector using the small pick tool to lift the lock tab (a lock tab is the small plastic catch that prevents accidental unplugging).
- Lift the duct out and set it aside.
Step 3: Pick the coil you’re replacing and unplug it
- Find the coil on top of the valve cover (a small rectangular module going straight into the engine).
- Use the small pick tool to gently lift the connector lock (if equipped), then press the release tab and pull the connector straight off.
- Tip: Wiggle the connector—don’t yank the wires.
Step 4: Remove the coil retaining bolt
- Use a 10mm socket with a 6" extension to remove the coil bolt.
- For the rear bank (near the firewall), use the universal joint swivel (1/4") if the ratchet angle is tight.
Step 5: Remove the coil from the spark plug
- Twist the coil slightly left/right to break the boot seal, then pull straight up.
- If it’s stubborn, pull upward while gently twisting—don’t pry hard on the plastic.
Step 6: Prep and install the new coil
- Put a pea-sized amount of dielectric grease inside the rubber boot (dielectric grease is a non-conductive grease that helps prevent moisture and makes future removal easier).
- Push the coil straight down onto the spark plug until you feel it seat.
Step 7: Reinstall the coil bolt and torque it
- Start the bolt by hand to avoid cross-threading.
- Use a torque wrench (in-lb) and 10mm socket: Torque to 89 in-lb (10 N·m).
Step 8: Reconnect the coil electrical connector
- Push the connector on until it clicks.
- Re-engage the connector lock (if equipped).
Step 9: Repeat for any other coils being replaced
- Replace coils one at a time so connectors don’t get mixed up.
- Tip: If you’re chasing a misfire, keep parts organized.
Step 10: Reinstall the intake duct and engine cover
- Reinstall the intake duct and tighten clamps using an 8mm socket (or flathead screwdriver).
- Reconnect any tube/connector you removed.
- Press the engine cover back onto its mounting grommets until fully seated.
✅ After Repair
- Reconnect the battery negative terminal (if disconnected) using a 10mm socket.
- Start the engine and let it idle for 1-2 minutes; it should be smooth with no shaking.
- If the check-engine light was on, use a scan tool to clear codes and confirm the misfire does not return.
- Test drive 10-15 minutes and recheck for warning lights.
💰 DIY vs Shop Cost
Shop Cost: $250-$700 (parts + labor, depending on how many coils)
DIY Cost: $40-$420 (parts only, depending on how many coils)
You Save: $150-$400 by doing it yourself!
Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 1.0-2.0 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.

















