Fiat 124 Spider - Page 75

FIAT 124 Spider
Engine Maintenance + Modification
75
be erratic during operation. Inspect the wires at every oil change and change if they are
suspect.
Rotor or Cap Failure
Old, brittle, or over-tight rotors can explode inside the distributor cap. They can spin
themselves to pieces. The contacts inside distributor caps can also become brittle over
time, as can the cap itself. Inspect and change them when necessary.
9.6.2 Conventional Ignition Failures
Points and Condensers
Poor operation, acceleration, and other running problems may be due to worn points.
Inspect the points for the appropriate gap and dwell. Check that the points show even
and not excessive wear. When replacing, change the condenser(s) at the same time.
9.6.3 Common Ignition Failures
Spark Plugs and Wires
Bad plugs and wires can arc, causing misfires and poor overall operation. Plug wires
should not be brittle or have any corrosion on the contacts. At night with the hood open
you should see no arcs between the wires and the engine body. There is no substitute
for high quality 7mm or 8mm wires like Magnecor or Bosch. The spark plugs should be
of the resistor type and free of corrosion. When removed from the engine they should
be very clean and with a brownish-white “burn” on the electrode.
Coil
Missing or poor combustion can be caused by a malfunctioning coil. The coil and
electronic coil pack are extremely durable and reliable units. The shop manual has
procedures for testing each unit. When replacing do not use any coil unit on the
electronic system not specifically designed for this purpose.
Poor Operation and Erratic Tachometer Display
Poor operation accompanied by a tachometer that is jumpy or otherwise erratic is often
caused by a short circuit inside the distributor body. On both electronic and conventional
distributors this may be caused by a broken rotor or metal in the cap. On the electronic
distributor this is usually caused by the wires leading to the pickup unit becoming frayed
and interfering with the metal advance plate.