P050A Idle speed off target just after a cold start

Cold start idle air control system performance

Monitor

P050A is a cold-start idle and emissions fault, and Kia, Hyundai and Subaru treat many cases as a logic problem fixed by an engine computer update, so it is usually safe to drive while you book a check.

It gets more serious if:

  • Inspect soon: Inspect soon if the engine stalls after a cold start or the idle surges up and down. Honda’s manual says a steady check engine light means you should get the car inspected promptly.

Source: how we rate severity

P050A in short

P050A means the idle speed was too far from the computer’s target just after a cold start. On Kia, Hyundai and Subaru models the usual fix is an engine computer update; otherwise air leaks, throttle deposits or idle control faults are common causes. It is usually safe to drive while you book a check.

Right after a cold start the engine computer holds idle at a target speed. GM’s logic sets P050A if actual idle stays about 100 rpm below or 200 rpm above the target for more than a second during that period, which matches the OBD rule for idle control faults.

Many P050A codes are logic, not parts. Kia reprogrammed 2012–2016 Soul and Rio engine computers, Hyundai revised the logic on the 2019 Sonata Hybrid, Subaru found clutch use and driving patterns right after start-up could set a false light, and Volkswagen updated 2011 Jetta software.

If no update applies, the checks are the same as for other idle faults: air leaks after the throttle, a dirty throttle body or restricted intake, PCV faults, and extra loads on the engine at idle.

Most likely causes

  1. Engine computer software that needs an update

    Supported by vehicle data
    Why it ranks here
    Kia (2012–2016 Soul and Rio), Hyundai (2019 Sonata Hybrid), Subaru (2011–2013 Legacy, Forester, Impreza) and Volkswagen (2011 Jetta) bulletins fix P050A by reprogramming the engine computer.
    What would change this
    Rises if a dealer finds your VIN is covered and the update has not been done. Falls if the software is current.

  2. Air leak into the intake after the throttle

    Common general cause
    Why it ranks here
    GM service information lists vacuum leaks among the first checks for P050A, and unmetered air pushes idle away from target.
    What would change this
    Rises if a smoke test finds a leak or fuel trim is well positive at idle. Falls if the intake holds smoke.
    How to test the vacuum hoses and intake leaks

  3. Dirty throttle body or restricted intake

    Common general cause
    Why it ranks here
    GM service information checks for throttle body deposits and a restricted air intake, which limit the air the computer can add at idle.
    What would change this
    Rises if the throttle bore is coated or the air filter or intake is blocked. Falls if they are clean.

  4. PCV fault or extra engine load at idle

    Possible — needs testing
    Why it ranks here
    GM service information also lists PCV faults and parasitic loads on the engine as things to rule out.
    What would change this
    Rises if idle changes when an accessory load is removed or the PCV system is faulty. Falls if not.
    How to test the crankcase ventilation (pcv) valve

What to test first

Start at step 1. Each result tells you what it means and where to go next.

  1. Ask a dealer whether your VIN has an engine computer update for P050A. Kia, Hyundai, Subaru and Volkswagen have issued them.

    Low risk

  2. Have the intake smoke-tested for leaks, and inspect the air filter, intake duct and throttle body for restriction or deposits.

    Best left to a shopTool: smoke machine, scan tool with live data

    Warning:Leak testing is done with the intake pressurised or the engine running near hot and moving parts. Let a shop do it.

  3. With a scan tool, command idle speed up and down (GM uses 600 to 1,400 rpm) and watch whether actual idle follows.

    Low riskTool: bidirectional scan tool

Symptoms

  • Check engine light with no change in how the car drives
  • Idle unusually high, low or uneven in the first minutes after a cold start
  • Engine stalls after a cold start or the idle surges Gets more serious: stop and have it checked.

Compare with: Rough idle with the check engine light on

How to fix

  1. Ask a dealer whether your VIN has an open engine computer update for P050A; Kia Soul owners can ask about service action SA485.

  2. With the engine off and cool, look over the intake hoses for cracks or a hose that has come off.

Parts and cost context

  • Vacuum hoses and intake leaks:Hoses and gaskets are cheap fixes, but find the leak with a smoke test before buying parts. Labour varies; get a quote.

Labor varies by vehicle and shop; get a quote before you approve a repair.

Compare used part prices on PartPriceGuide

On your vehicle

Kia

  • 2012–2016 · Soul

    Supported by vehicle data

    Kia has several engine computer updates for P050A on the 1.6L GDI Soul, the latest being service action SA485 for 2014–2016 models. Ask a dealer to check your VIN before replacing parts. Whether the bulletin is still current is not verified.

  • TSB FUE053Status unverified

    1.6L GDI MIL on with P050A: ECM logic improvement (SA485)

    2014–2016soul · issued · NHTSA 10201528

    Update the engine computer logic on 2014–2016 Soul (PS) 1.6L GDI built 29 August 2013 to 26 July 2016.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • TSB-ENG118R2Status unverified

    Rio, Soul 1.6 GDI MIL on with P050A and other codes (SA152)

    2012–2013soul, rio · issued · NHTSA 10109699

    Engine computer software upgrade for P0456, P0461, P050A, P2188, P2192 and P0128.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • TSBENG146R1Status unverified

    ECM upgrade: Rio, Soul MIL on with P050A and other codes

    2012–2014rio, soul · issued · NHTSA 10089747

    Reprogram the engine computer for VINs in the listed production ranges.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

Subaru

  • 2011–2013

    Supported by vehicle data

    On 2011–2013 Legacy, Forester and Impreza, Subaru says P050A can be a false light from clutch use or driving right after start-up, fixed by reprogramming. Whether the bulletin is still current is not verified.

  • 11-135-13Status unverified

    ECM reprogramming for false MIL with P050A

    2011–2013legacy, forester, impreza · issued · NHTSA 10093678

    P050A can set from clutch operation (manual) or driving patterns right after start-up; reprogram the engine computer.

    We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

  • P0507Idle speed higher than the computer is aiming for

    Same system Common general cause

    GM covers P0506, P0507 and P050A in one idle control procedure; P050A is the cold-start version of an idle speed fault.

  • P0128Engine coolant stays below thermostat temperature

    Shares causes Supported by vehicle data

    Kia’s 2012–2014 Rio and Soul software bulletins list P050A with P0128 and other codes fixed by the same engine computer update.

All Vehicle speed, idle control and engine electrical codes

P050A questions

Is it safe to drive with P050A?

Usually, if the car starts and drives normally. Get it checked soon if it stalls after cold starts.

Why does my Kia Soul keep setting P050A?

Kia has issued several engine computer updates for P050A on the 1.6L GDI Soul. Ask a dealer whether your VIN has one outstanding.

Sources and review

  1. Kia TSB FUE053 (SA485): 1.6L GDI MIL on with P050A, ECM logic improvement (2014–2016 Soul) — Kia America / NHTSA ,
  2. Subaru bulletin 11-135-13: ECM reprogramming for false MIL with P050A (2011–2013 Legacy, Forester, Impreza) — Subaru of America / NHTSA ,
  3. Final Regulation Order: 13 CCR §1968.2, Malfunction and Diagnostic System Requirements (OBD II), 2004 and subsequent model-year passenger cars, light-duty trucks and medium-duty vehicles (2015 amendments) — California Air Resources Board
  4. Troubleshoot Idle Speed Control System — AA1Car.com (Larry Carley)
  5. 2023 Integra Owner's Manual: Indicator, Coming On/Blinking — American Honda Motor Co.
  6. Kia TSB ENG146R1: ECM upgrade, Rio and Soul MIL on with P050A and other codes (2012–2014) — Kia America / NHTSA ,
  7. Hyundai TSB 20-FL-005H: ECM update revising P050A logic (2019 Sonata Hybrid, Plug-in Hybrid) — Hyundai Motor America / NHTSA ,
  8. Volkswagen bulletin TB011322: update programming to eliminate P050A (2011 Jetta) — Volkswagen of America / NHTSA ,
  9. DTC P0506, P0507 or P050A (without LF1/LFW), 2011 Saab 9-4X service information — Saab Automobile / General Motors (Saab WIS online archive)
  10. Vacuum Leaks — AA1Car.com (Larry Carley)
  11. Kia TSB ENG118R2 (SA152): Rio, Soul 1.6 GDI MIL on with P0456, P0461, P050A, P2188, P2192, P0128 — Kia America / NHTSA ,
Last reviewed
Written by
Saurabh K.
Editorial review
Pending
Technician review
Technician review pending

This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error

My Car

Pick your car and code pages will point out notes and bulletins for it. Saved only in this browser.

Fill this in from your VIN

Used once to identify your engine; not stored.