94 Camry no spark

Answer 1

There are three common sources of no spark on all cylinders:

• failure of the coil,
• failure of the ignition control module ("ignitor"), or
• the button contact in the distributor cap is sticking.

The ignitor is an expensive part to replace (list is over $400), and some less-common failures are difficult to diagnose. The common failures are easily diagnosable since there is a tachometer output and engine computer gets a feedback signal indicating that the ignitor thinks it has triggered a spark. Indications that it's still good are if

• the tach jumps when cranking the engine, and
• if there are no engine computer error codes.

The ignitor is mounted on the left strut tower where it's easily seen, but you'll need to unclip the air filter cover to remove it.

The coil is less expensive, but it's inside the distributor and thus more difficult to replace. You'll need to remove the air filter cover then the distributor cap to test the coil. The primary should measure less than 1 ohm between the screw terminals, and the secondary should measure between 9K and 15K ohms between either screw terminal and where the distributor cap button makes contact. A resistance lower than 9K ohms indicates the coil has at least partially failed and should be replaced.

Tools to replace coil and distributor parts

• #2 Phillips screwdriver for coil mounting screws
• 7mm (1/4") nut driver for coil terminals
• 8mm driver (or #2 Phillips) for distributor cap screws
• 10mm socket (or #3 Phillips) for air duct clamp
• 12mm socket and 3"+ extension for distributor hold-down bolts
• 12mm open-end wrench for throttle cable
• Small screwdriver or plastic tool to remove the distributor o-ring and release plug wires from distributor cap