Au7o mascotAu7o
Known IssuesDiagnose my car
  1. Au7o
  2. /
  3. Known Issues
  4. /
  5. P1520
P1520ModeratePowertrain

P1520 on 2000-2003 BMW M5 — Intake Manifold Runner Control Circuit Fault

1 vehicles · 1 makes · $900-$3,000 repair

Share:@au7o.io
NewAI Photo & Video Diagnosis
Not sure this is what you've got?
Upload a photo or video — Au7o will confirm the match and check for other common failures at the same time.
Upload & confirm

Most Reported On

2000-2003BMW M5

P1520 is an OBD-II diagnostic trouble code meaning “Intake Manifold Runner Control Circuit Fault.” This manufacturer-specific code (common on Ford) indicates a circuit fault in the Intake Manifold Runner Control (IMRC) system, which uses motorized or vacuum-actuated flaps in the intake to vary airflow length for better low- and high-RPM performance. The computer detected that the IMRC actuator circuit is open, shorted, or not responding as commanded. You may notice reduced power, hesitation, or poor throttle response, though some drivers feel nothing. It is generally an electrical or actuator/linkage issue rather than internal engine damage. This code is most commonly reported on 2000-2003 BMW M5, with repair costs ranging from $900 to $3,000.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (1)
  • Related Codes
  • FAQ
  • Sources (1)
Back to top

Common Causes

1Faulty IMRC actuator or motor
2Open or shorted IMRC wiring harness
3Poor or corroded electrical connection at the actuator
4Stuck, broken, or seized runner flaps/linkage
5Carbon buildup binding the runner plates
6Faulty ECM/PCM driver (less common)

Typical Repair Cost

$900 - $3,000

Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose P1520, you'll need an OBD-II scanner. Here are our recommendations at every price point.

Budget Pick$10–$20

ANCEL AD310 Classic OBD-II Scanner

by ANCEL

A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).

  • Read & clear engine codes
  • View freeze frame data
  • I/M readiness status
  • No batteries or app needed
Check Price on Amazon
Best Value$90–$120

BlueDriver Pro Bluetooth Scanner

by BlueDriver

Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.

  • Enhanced diagnostics (ABS, SRS, transmission)
  • Repair Reports with verified fixes
  • Smog check readiness
  • Free app (iOS & Android)
Check Price on Amazon
Advanced$180–$230

LAUNCH CRP123X OBD-II Scanner

by LAUNCH

A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.

  • Engine, transmission, ABS, SRS diagnostics
  • Live data stream & graphing
  • AutoVIN for vehicle identification
  • Free lifetime updates via Wi-Fi
Check Price on Amazon
Professional$350–$450

Autel MaxiCOM MK808S Diagnostic Tool

by Autel

Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.

  • All-system diagnostics (25+ modules)
  • Bi-directional control & active tests
  • Oil reset, EPB, BMS, TPMS, injector coding
  • 7-inch touchscreen with Android OS
Check Price on Amazon

As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.

Vehicles Affected (1)

BMW P1520 page →
M5Critical

E39 M5 VANOS Solenoid/Seal Failure Causing Rattle, Power Loss, and Check Engine Lights

2000-2003$900-$3,0000 reports

Related Codes (8)

P1523Variable Cam Timing (VCT/IVC) Solenoid Stuck / Circuit MalfunctionP0020Camshaft Position 'A' Actuator Circuit (Bank 2)P0034Turbocharger/Supercharger Bypass Valve Control Circuit LowP0035Turbocharger/Supercharger Bypass Valve Control Circuit HighP003ATurbocharger/Supercharger Boost Control 'A' Position Exceeded Learning LimitP0046Turbocharger/Supercharger Boost Control 'A' Circuit Range/PerformanceP0089Fuel Pressure Regulator 1 PerformanceP0093Fuel System Leak Detected - Large Leak

FAQ

What does P1520 mean?

P1520 stands for "Intake Manifold Runner Control Circuit Fault." This manufacturer-specific code (common on Ford) indicates a circuit fault in the Intake Manifold Runner Control (IMRC) system, which uses motorized or vacuum-actuated flaps in the intake to vary airflow length for better low- and high-RPM performance. The computer detected that the IMRC actuator circuit is open, shorted, or not responding as commanded. You may notice reduced power, hesitation, or poor throttle response, though some drivers feel nothing. It is generally an electrical or actuator/linkage issue rather than internal engine damage.

What are the most common causes of P1520?

The most common causes of P1520 are: Faulty IMRC actuator or motor, Open or shorted IMRC wiring harness, Poor or corroded electrical connection at the actuator, Stuck, broken, or seized runner flaps/linkage, Carbon buildup binding the runner plates, Faulty ECM/PCM driver (less common). The specific cause varies by vehicle.

How much does it cost to fix P1520?

Repair costs for P1520 range from $900 to $3,000, depending on the vehicle and root cause.

Which vehicles are affected by P1520?

Au7o has documented P1520 across 1 vehicle models from 1 manufacturers: BMW.

Sources (1)

  • ForumBMW M5Board discussion: VANOS issues on S62 / startup rattle and repair experiences

Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

Known IssuesDTC LookupDrivePricingAboutTermsPrivacyCookiesConsentData rightsCopyrightFeedback
Share:@au7o.io

Vehicle data and repair guidance on this site are compiled with AI assistance and may contain errors. Always verify with your service manual or a qualified mechanic.

Au7o · 2026
Built for DIY mechanics. Privacy-first.

© 2026 Au7o. All rights reserved.