Hard Start

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

PRELIMINARY CHECKS
- Perform the careful visual/physical checks.
- Make sure the driver is using the correct starting procedure.

SENSORS
Check the following:
- Engine Coolant Temperature (ECT) Sensor. Using a "Scan Tool", compare coolant temperature with ambient temperature on cold engine. If coolant temperature reading is 5 degrees greater than or less than ambient air temperature on cold engine, check for high resistance in coolant sensor circuit or sensor itself. Compare resistance value to the chart in Diagnostic Trouble Code (DTC) 14.
- Manifold Absolute Pressure (MAP) sensor. Check for flooding and/or correct sensor for vehicle.
- Throttle Position (TP) sensor for binding or a high TP sensor voltage with the throttle closed (should read between 0.54 volts and 1.25 volts.)

FUEL SYSTEM
Check the following:
- Fuel Pump (FP) relay operation - pump should turn "ON" for 2 seconds when ignition is turned "ON". Use chart A-5
- Fuel Injectors are correct for the vehicle.
- Fuel pressure, Use chart A-7.
- Contaminated fuel.
- Engine fuse (visual inspect).
- Faulty in-tank Fuel Pump check valve will allow the fuel in the lines to drain back to the tank after engine is stopped. To check for this condition, perform Fuel System Diagnosis chart A-7.

IGNITION SYSTEM
Check the following:
- For proper ignition voltage output with spark tester J-26792 or equivalent (ST-125).
- Spark plugs. Remove spark plugs, check for wet plugs, cracks, wear, improper gap, burned electrodes, or heavy deposits. Repair or replace as necessary.
- Bare or shorted wires.
- Loose ignition coil ground.

ADDITIONAL
Check the following:
- Idle Air Control operation, chart C-2C.
- Basic engine problem.
- Technical Service Bulletins (TSBs) for calibration updates.