Hard to Start

SYMPTOM DEFINITION:
Engine cranks OK, but does not start for a long time. Does eventually run, or may start but immediately dies.

PRELIMINARY CHECKS
- Refer to Diagnostic Notes. Initial Inspection and Diagnostic Overview
- Make sure the driver is using the correct starting procedure.

SENSORS
Check:
- Engine Coolant Temperature (ECT) sensor - Using a scan tool, compare engine coolant temperature.
- If coolant temperature reading is 5 degrees greater than or less than ambient air temperature on a cold engine, check for high resistance in coolant sensor circuit or sensor itself. Refer to "DTC 15" and compare resistance values. Powertrain Controls - ECM/PCM
- Throttle Position (TP) sensor - If a sticking throttle shaft or binding linkage causes a high TP sensor voltage (open throttle indication), the control module will not control idle. Monitoring TP sensor voltage. Scan tool and/or voltmeter should display less than 0.85 volt with throttle closed.

FUEL SYSTEM
Check:
- Fuel pump relay operation. Fuel pump should operate for 20 seconds on vehicles with a fuel module and for 2 seconds on all other vehicles when ignition is turned "ON." Refer to "Chart A-5." Chart A-5 Fuel Pump and Relay Electrical Test
- Fuel pressure. Refer to "Chart A-6." Related Tests, Information and Procedures
- For water contaminated fuel.
- Fuel pump relay - Connect test light between fuel pump "test" terminal and ground. Test light should be "ON" for 2 seconds following ignition "ON." If not, refer to "Chart A-5." Chart A-5 Fuel Pump and Relay Electrical Test

IGNITION SYSTEM
Check:
- Ignition system for:
- Proper ignition voltage output with spark tester J 26792 or equivalent (ST 125).
- Spark plugs; wet plugs, cracks, wear, improper gap, burned electrodes or heavy deposits.
- Bare and shorted wires.
- Moisture in distributor cap.
- Worn distributor shaft.
- Pickup coil resistance and connections.
- Loose ignition coil connections.
- CKT 423 (ignition control) for short to ground.

ADDITIONAL CHECKS
Check:
- IAC operation - refer to "DTC 35." Powertrain Controls - ECM/PCM
- EGR operation - System Diagnosis - Exhaust Gas Recirculation (EGR) System
- Service Bulletins for PROM updates.