Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DBβ LIVE
HOMESERVICE MANUALSTOYOTA2001HIGHLANDER 2WD L4-2.4L (2AZ-FE)REPAIR AND DIAGNOSISPOWERTRAIN MANAGEMENTTUNE-UP AND ENGINE PERFORMANCE CHECKSSPARK PLUGTESTING AND INSPECTION
2001 Toyota Highlander 2WD L4-2.4L (2AZ-FE)
Spark Plug: Testing and Inspection
2001 Toyota Highlander 2WD L4-2.4L (2AZ-FE)SECTION Testing and Inspection
SPARK PLUG [19100P / 98-34]
NOTE: Try not to clean the irridium and platinum tip. However, when the cleaning is necessary, use of spark plug cleaner is recommended. Duration should be less than 20 seconds.

a. Check the spark plug for thread damage and insulator damage.
If abnormal, replace the spark plug.
Recommended spark plug:
DENSO MADE...............SK20R11
NGK MADE.................IFR6A11

b. Check the electrode gap.
Electrode gap:......1.0 - 1.1 mm (0.039 - 0.043 in.)
Maximum electrode gap:.......1.2 mm (0.047 in.)
NOTE: This engine is fitted with irridium-tipped spark plugs Never attempt to adjust the electrode gap.
Do not scratch the irridium and platinum tip between electrode gap.
NOTE: Try not to clean the irridium and platinum tip. However, when the cleaning is necessary, use of spark plug cleaner is recommended. Duration should be less than 20 seconds.
a. Check the spark plug for thread damage and insulator damage.
If abnormal, replace the spark plug.
Recommended spark plug:
DENSO MADE...............SK20R11
NGK MADE.................IFR6A11
b. Check the electrode gap.
Electrode gap:......1.0 - 1.1 mm (0.039 - 0.043 in.)
Maximum electrode gap:.......1.2 mm (0.047 in.)
NOTE: This engine is fitted with irridium-tipped spark plugs Never attempt to adjust the electrode gap.
Do not scratch the irridium and platinum tip between electrode gap.
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.