Chart 1
Diagnostic Chart (Part 1 Of 5):
Schematic:
In order to diagnose this system, battery voltage must be above 11 volts. Cranking speed of the starter must be normal and fuel quality and quantity should be checked. When ignition is On and crank pulses are received, IC pulses are delivered to the EI module. Also pulses are delivered to the injectors when crank pulses are received.
DIAGNOSTIC AIDS
Water in the fuel can cause a no start during cold weather starts.
An ECT sensor reading incorrectly can cause a no start or a hard start. This may be due to over-fueling or under-fueling.
ECT may be compared to IAT temperature with scan tool if engine has cooled overnight at ambient temperature. They should be within 4 degrees of each other with ignition On and engine Off.
TEST DESCRIPTIONS
1. An IC fault will cause two mating cylinders to not spark and may result in a no start especially if the engine is cold.
2. If no rpm is indicated spark and injectors will not be turned On. (No 7x signal to the PCM from the EI module.)
3. Check for a flooded engine (fouled plugs).
IMPORTANT: Always check fuses first in the IP and Underhood fuse blocks.