P0505 Code: Idle Control System

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P0505 stands for “Idle Control System.”  

The idle control system is an important part of your car’s engine. It makes sure that when you’re driving around town, your engine operates at the right speed for optimal fuel efficiency and performance. The idle control system does this by regulating the speed of the vehicle’s crankshaft, which turns over its pistons to get them moving up and down. When everything is working properly, your idle should stay steady even if you step on the gas pedal or release it; if not, there could be a problem with your vehicle’s idle control system.

What You'll Read About

What is the P0505 code?

The P0505 code is a generic code for the idle control system. It indicates that there is something wrong with your car’s engine, but does not provide any information about what specifically might be wrong or how to fix it. In most cases, this means that you should take your vehicle into a shop so they can diagnose and repair it for you.

What are the causes of the P0505 code?

  • Fuel system: The fuel system may be contaminated with water, or the fuel filter could be clogged.
  • Throttle position sensor: The throttle body may be damaged or defective.
  • Idle air control motor (IAC): This device helps control engine idle speed by using a motor that opens and closes an air bypass valve inside the throttle body to enrich or lean out your engine’s air/fuel mixture. If it’s not working properly, you’ll get this code stored in memory as well as poor performance from your vehicle when starting up after sitting for some time; it might also cause rough idling if left unrepaired for too long.
  •  Idle Speed Control Valve (ISCV): This part is responsible for regulating the amount of air entering into an engine at idle—too much will cause poor fuel economy while too little will lead to stalling issues.
  • Engine misfire: A misfire occurs when one or more cylinders aren’t firing properly due to bad spark plugs, dirty injectors or leaky valve seals among other things; if this happens then we’ll see P0505 pop up on our scanner!

How does a mechanic diagnose the P0505 code?

The mechanic will first check the engine’s coolant temperature. If it’s below normal, then the PCM (powertrain control module) will set a code and illuminate the MIL (malfunction indicator lamp). Next, he’ll inspect the oxygen sensor for wear or damage, as well as ensure that there isn’t any debris blocking its connection to the exhaust manifold. He may also check your air intake hose for cracks or holes that would prevent proper airflow into your engine’s cylinders during combustion cycles.

Finally, he’ll inspect both sides of your idle air control valve using an ohmmeter to make sure they’re opening and closing properly–if one side doesn’t work at all while another works fine then this could indicate that only half of your IACV needs replacing instead of both halves being bad at once.

What repairs can fix the P0505 code?

  • Reset the idle control system
  • Replace the idle control valve
  • Replace the idle control motor
  • Replace the idle control sensor

Conclusion

The idle control system is an important part of your car. It keeps the engine running smoothly and prevents it from stalling out or dying unexpectedly. The P0505 code means that there is a problem with this system, so it should be checked out as soon as possible by a mechanic if you see this code appear on your dashboard.