Symptoms
A tick-tick or pop-pop at cold start that sounds like an exhaust leak and, as the plug loosens, doesn't go away when warm. Premature coil-boot and coil failures.
The fix, step by step
- Pull the coils and check every plug's torque.
- If one is loose, replace the set and torque them correctly; the thread quotes the factory spec as 13 ft-lb.
- If the tick is still there afterward, then look for an exhaust leak.
- A plug that has blown out usually needs a thread insert in the head.
Tools & part numbers
- Spark-plug socket and extension
- torque wrench (inch-pound range)
- dielectric grease for the coil boots.
Where to buy the parts
Toyota iridium spark plug 90080-91180 (×8)LexusPartsNow (OEM) ↗Amazon ↗
Spark plug tube seal, 2UZ (VCC50010OEM) — if a valve cover is offCruiserTeq ↗Amazon ↗
Hunting a used or discontinued part? Search eBay Motors for Toyota Land Cruiser 100 Series parts →
Rated for a competent home mechanic with a decent tool kit. Confirm torque figures, fluids and procedures against the factory service manual for your VIN, support the truck on stands rather than a jack, and work at your own risk (disclaimer). Some parts links are affiliate links, which pay us a small commission at no cost to you.