Fast Idle Or Slow Return To Idle
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2003 Ford Pickup, 2003 Ford F550 Super Duty, 2003 Ford F450 Super Duty, 2003 Ford Excursion, and 2003 Ford Econoline. However, it is still accessible from the selected car via links, so may be relevant.
- Preliminary Checks
Check for binding or stuck accelerator pedal. Check for broken accelerator return spring. Ensure floor mats do not interfere with accelerator pedal. Ensure engine is not being supplied from an external fuel source. Check if engine is reaching normal operating temperature. Ensure power take-off and charge protect devices are disengaged. Repair any problems as necessary. If no problems are indicated, go to next step. - Perform Quick Test
Perform QUICK TEST in SELF-DIAGNOSTICS - 7.3L DIESEL article. If any DTCs are present, go to DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 7.3L DIESEL article and perform appropriate SYSTEM TESTS. If no DTCs are present, go to next step. - Check Accelerator Pedal
Check and repair accelerator pedal as necessary. If okay, go to next step. - Check Crankcase
Check for overfilled crankcase. If crankcase is not overfilled, go to next step. If crankcase is overfilled, drain crankcase to correct level and determine cause of overfill. - Check Engine Oil For Coolant
Check engine oil for coolant. If coolant is not present in engine oil, go to next step. If coolant is present in engine oil, diagnose source of coolant. Repair as necessary. - Check For Fuel Contamination
Check fuel for contamination. Perform TEST 2: SUFFICIENT CLEAN FUEL under ENGINE PERFORMANCE DIAGNOSTIC PROCEDURES in SYSTEM & COMPONENT TESTING - 7.3L DIESEL article. If fuel is not contaminated, go to next step. If fuel is contaminated, drain and refill fuel system as necessary. - Check Parameter Identifications (PIDs)
Warm engine to normal operating temperature. Using scan tool, access and monitor EOT PID. See PARAMETER IDENTIFICATION MODE under ADDITIONAL SYSTEM FUNCTIONS in SELF-DIAGNOSTICS - 7.3L DIESEL article. If EOT sensor value is 100°F (38°C) or more, go to next step. If EOT sensor value is less than 100°F (38°C), replace EOT sensor. EOT sensor is located on left side of engine. See Figure. - Check Turbocharger
Remove turbocharger inlet air duct. Inspect turbocharger compressor wheel for damage to blade or for signs that blade has been rubbing turbocharger housing. If damage is present, replace turbocharger. If turbocharger is okay, no problem is indicated. Return to SYMPTOM DIAGNOSIS if a symptom still exists.