Engine-Codes - Ford - P0505 1999 FORD F150

P0505 1999 FORD F150 - Idle Air Control System Malfunction

Repair Importance Level: 3/3
Repair Difficulty Level: 2/3  What is this?
Table of contents

P0505 1999 FORD F150 Possible Causes

  • Check for Vacuum Leaks
  • Faulty Idle Air Control (IAC) Valve
  • Idle Air Control Valve harness is open or shorted
  • Idle Air Control Valve circuit poor electrical connection
  • Faulty Powertrain Control Module (PCM)

How is the P0505 1999 FORD F150 code repair?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

Tech Notes





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What is the cost to diagnose the P0505 1999 FORD F150 code

Labor: 1.0

The cost to diagnose the P0505 1999 FORD F150 code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.

Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)
  • Engine hard to start
  • Rough or erratic idle speed

P0505 1999 FORD F150 Meaning

The Idle Air Control (IAC) valve assembly is used to control idle speed and provide a dashpot function. IAC valve assembly meters inlet air around the throttle plate through a by-pass within the IAC valve assembly and throttle body.
The Powertrain Control Module (PCM) determines desired idle speed or air by-pass and signals the IAC valve assembly through a specified duty cycle. The IAC solenoid is built into the IAC valve assembly. IAC solenoid responds by positioning the IAC valve to control the amount of air by-passed. PCM monitors engine speed and adjust the IAC duty cycle to achieve the desired RPM. IAC valve assembly is not adjustable and cannot be cleaned. The Diagnostic Trouble Code (DTC) will set when the IAC valve assembly is not operating properly.

More Information

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