Product Description
Ignition Monitor Relay Bypass - 89 to 95
was 928 615 175 00
#28 on the PET Drawing
The 89 to 95 cars have two separate ignition circuits. Ignition circuit 1 covers the right bank, distributor & coil. Ignition circuit 2 covers the left bank, distributor & coil. If there is a failure in one of the ignition circuits, raw fuel is pumped out of the cylinders and into the exhaust system. Raw fuel and hot catalytic converters do not work well together = fire!!
There are two temperature sensors (#35 on the PET Drawing) on each head. They detect when there is a difference in temperature between the two heads. All four sensors are well known as failure items. They are expensive to replace at $500 each. Not worth replacing.
Porsche now provides a "bypass" relay to deactivate the system so no further
issues arise. There is a large perspex relay #27 next to the LH computer - remove the relay and insert the bypass.
