How to Troubleshoot a Toyota Camry

by Steven Redlon

Troubleshoooting your Toyota Camry may sound like a an overwhelming task. Starting with the basics and following diagnostic procedures detailed in any Chilton repair manual will give you a clear picture of what is involved.Through process of elimination, determining a solution should not be difficult.

Diagnosing 4 or 6 cylinder Camry Sparkplugs and Wires

Open the hood and remove plastic engine cover with an 10mm socket. Remove spark plug wires by pulling in an upward motion.If its a newer model Camry, you may have a coil-on-plug ignition system. To remove these, unclip the wire harness from the coil, and gently pull back, disconnecting the wire from the coil. Remove the coils using a 1/4-inch 10mm deep well socket and ratchet.

Attach 19 mm 3/8th drive spark plug socket to 6 inch 3/8 drive extension, and then clip to the head of the 3/8th drive ratchet. Remove spark plugs by inserting ratchet into each individual cylinder.

With all four spark plugs removed check for spark tracking, burnt electrode and corroison or carbon build up on the tips. Spark tracking can be detected by a very dark line running down the side of the porcelin casing of the spark plug. Spark tracking is usually caused by a bad spark plug wire or coil. Reinstall spark plugs in opposite of removal.

Inspect spark plug wires by looking at the electrodes of the wires, any fraying in the wires insulation or burn marks, which can short a plug wire.


  • close If you try and remove spark plug wires with the engine running, you will get shocked. Also always check spark plug gap before installing new plugs. Although most new spark plugs come pre-gapped, you will have no idea of knowing if one of those plugs has been dropped prior to your purchase. Spark plug specifications can usually be found on the emssions label located underneath the hood.

Items you will need


About the Author

Steven Redlon has been writing since 2006. He contributes monthly to How I See It, the "Star Exponent" op/ed page. Steven also studied refrigeration and mechanics at the US Army OC+S, Aberdeen Proving Ground Maryland, and achieved veteran status for his support role during the Bosnia campaign.

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Photo Credits

  • photo_camera old spark plugs image by Rog999 from