Chart A-3A Engine Cranks But Will Not Run

CIRCUIT DESCRIPTION
Battery condition and engine cranking speed are OK, and there is adequate fuel in the tank. If engine starts but immediately stalls, see Symptoms (Hard Start).

CHART TEST DESCRIPTION
1. A "CHECK ENGINE' light "on" is a basic check for ignition and battery supply to the Electronic Control Module (ECM).

2. No spark indicates a basic HEI problem.

3. This test will determine if the ECM is receiving the reference signal and controlling the injectors. If the test light "blinks" while cranking, then ECM control should be considered OK. How bright the test light "blinks" is not important. However, the test light should be a J-34730-2 or equivalent.

4. Use pressure gage J-34730-1. Wrap a shop towel around the fuel pressure tap to absorb any small amount of fuel leakage that may occur when installing the gage.

5. Diagnostic aids:
^ An EGR valve sticking open can cause a high air/fuel ratio during cranking. Unless engine enters "Clear Flood" at the first indication of a flooding condition, it can result in a no start.

^ Check for fouled plugs.

^ If the TPS is sticking or binding in the wide open throttle position, the ECM will be in the "Clear Flood" mode. In this mode the fuel is completely turned off which would cause a no start.

^ A defective cold start circuit or water in fuel line can cause a no start in cold weather.

^ To check cold start circuit:
- Disconnect distributor 4-way connector.
- Engine temperature below 30°C (86°F).
- Fuel pressure gage installed.
- IGN. "on".
- Crank engine for 2 seconds and note gage.
- If the cold start valve is functioning properly the pressure should drop at least 5psi (34 kpa).

If not OK, see Chart A-9.

- Also check that injectors on both sides of engine will cause a test light to "blink".

If above are all OK, refer to Symptoms, "Hard Start".