P0024 on 2015-2021 Ford Expedition: Causes and Fixes for Camshaft Timing

What's Unique About the 2015-2021 Ford EXPEDITION

The 3.5L EcoBoost engine in the Expedition relies heavily on its Variable Camshaft Timing (VCT) system for both performance and efficiency. This system is notoriously sensitive to oil quality and pressure. Ford has issued multiple Technical Service Bulletins (TSBs) acknowledging that small debris in the oil can cause the VCT solenoids to stick, directly leading to codes like P0024. [SSM 47170, SSM 50067] This makes regular, high-quality oil changes especially critical on these engines to prevent timing-related issues. Some owners on forums have even resorted to engine flushes with ATF or other chemicals to clear sludge from VCT passages as a last-ditch effort before parts replacement.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle. 👇

Generation note: This range covers two Expedition generations. The 2015-2017 models (Third Generation) use the first-gen 3.5L EcoBoost. The 2018-2021 models (Fourth Generation) use the updated second-gen 3.5L EcoBoost, which features a revised fuel system and other changes. While the underlying cause of P0024 is the same (VCT system), the specific part numbers for VCT solenoids may differ. The Gen 2 EcoBoost (2017+ F-150, 2018+ Expedition) uses part HL3Z-6M280-A for all four VCT solenoids.

Symptoms You May Notice

• Check Engine Light is on
• Rough or unstable idle
• Engine stalling, especially at low speeds
• Hesitation or loss of power during acceleration
• Hard starting condition
• Decreased fuel economy
• Rattling, knocking, or grinding noises from the engine

Most Likely Causes

1. Low or Dirty Engine Oil 🔴 High Probability The VCT system uses oil pressure to adjust timing. TSBs confirm that debris in the oil can cause solenoids to stick. [SSM 47170, SSM 50067] Using the wrong viscosity or extending oil change intervals can lead to sludge and blockages that clog the tiny passages in the VCT solenoids and phasers.
   How to confirm: Check the engine oil level on the dipstick and inspect its condition. If it's low, excessively black, or appears sludgy, it needs to be changed. This should always be the first step.
   Typical fix: Perform an oil and filter change using the correct viscosity full-synthetic oil specified by Ford (e.g., Motorcraft 5W-30 Full Synthetic) and a quality filter (e.g., Motorcraft FL-500S).
   Est. part cost: $50-$100
2. Faulty VCT Solenoid (Bank 2 Exhaust) 🔴 High Probability → Shop Engine Variable Valve Timing (VVT) Solenoid As noted in Ford TSBs SSM 47170 and SSM 50067, these solenoids are known to stick due to small debris in the engine oil, causing them to fail in an open or closed position. This is the most common component failure for this code.
   How to confirm: Use a diagnostic scan tool to command the solenoid on and off while monitoring the camshaft angle. A common DIY method is to swap the Bank 2 exhaust solenoid with the Bank 2 intake solenoid. If the code changes to P0021 (Intake Camshaft Over-Advanced), the solenoid is confirmed bad. You can also test the solenoid's internal resistance with a multimeter; a typical reading is between 6.9 and 7.9 ohms.
   Typical fix: Replace the Bank 2 exhaust VCT solenoid. 🎬 See this step-by-step walkthrough for replacing the exhaust solenoids. It is highly recommended to replace all four VCT solenoids at the same time due to labor overlap and similar wear patterns.
   Est. part cost: $40-$85 per solenoid
3. Wiring or Connector Issue at VCT Solenoid 🟡 Medium Probability → Shop Engine Variable Valve Timing (VVT) Solenoid Engine bay heat and vibration can cause wiring to become brittle or connectors to loosen over time. The solenoid connectors are located on the front of the valve covers and are exposed to the elements.
   How to confirm: Visually inspect the wiring harness and connector for the Bank 2 exhaust VCT solenoid. Check for frayed wires, corrosion, or a loose connection. Use a multimeter to check for proper voltage (12V with ignition on) and ground at the connector.
   Typical fix: Repair the damaged wiring or clean/replace the connector pigtail.
   Est. part cost: $5-$50

Rare But Worth Checking

• Failing Camshaft Phaser: → Shop Engine Camshaft This is a more serious mechanical failure. The phaser is the gear on the end of the camshaft that the VCT solenoid controls. Cam phaser issues, including a loud "cold-start rattle", are a notorious problem on the 3.5L EcoBoost. If a new solenoid and clean oil don't fix the code, the phaser itself may be stuck or its internal locking pin failed, requiring a major timing job to replace.
• Stretched Timing Chain: → Shop Engine Timing Chain While less common than phaser or solenoid issues, a stretched timing chain can cause the base timing to be off, leading to a variety of camshaft position codes. This is often accompanied by a startup rattle and is a major repair that usually includes replacing the phasers, guides, and tensioners at the same time.

Diagnosis Steps

1. Check Engine Oil: Verify the oil level is full and the oil is clean. If low or dirty, perform an oil and filter change with the correct Ford-spec oil (e.g., Motorcraft 5W-30). Clear the code and see if it returns.
2. Scan for Codes: Use an OBD-II scanner to confirm P0024 and check for any other related codes. Note any correlation or bank-to-bank codes.
3. Inspect Wiring: Visually inspect the electrical connector and wiring going to the Bank 2 (driver's side) exhaust VCT solenoid. Look for any damage, corrosion, or loose connections. The exhaust solenoid is the one closer to the exhaust manifold.
4. Diagnostic Swap: A common and effective DIY step is to swap the Bank 2 exhaust VCT solenoid with the Bank 2 intake VCT solenoid. They are located next to each other on the front of the driver's side valve cover. Clear the codes and drive the vehicle. If the code changes to P0021, you have confirmed the solenoid is the faulty part.
5. Test the Solenoid: If you have a capable scan tool, command the solenoid on and off to see if it's functioning. You can also remove the solenoid and apply 12V to its terminals; you should hear a distinct click as the internal plunger moves. 🎬 Watch: How to identify a failed VCT solenoid. Resistance should be 6.9-7.9 ohms.
6. Advanced Diagnosis: If a new solenoid and clean oil do not resolve the issue, the problem is likely more severe, such as a failing camshaft phaser or a timing chain issue. This level of diagnosis often involves checking for the 'cold start rattle' and may require professional tools to measure timing chain stretch and phaser performance directly.

Parts You'll Likely Need

• Variable Camshaft Timing (VCT) Solenoid (OEM #HL3Z-6M280-A) — This solenoid is the most common point of failure for code P0024, often sticking due to oil debris as cited in Ford TSBs. [SSM 47170, SSM 50067] This part number is applicable to the 2nd Gen 3.5L EcoBoost (2018-2021 Expedition).
  Trusted brands: Motorcraft, Dorman
  OEM price range: $50-$85
  Aftermarket price range: $30-$60
• Engine Oil and Filter (OEM #Motorcraft 5W-30 Synthetic Blend, Motorcraft FL-500S) — Low or dirty oil is a primary cause of VCT system faults. Using the correct full-synthetic oil and a quality filter is crucial preventative maintenance and a required first step in diagnosis.
  Trusted brands: Motorcraft, Mobil 1, Pennzoil
  OEM price range: $60-$100
  Aftermarket price range: $50-$80
• Valve Cover Gasket — The valve cover must be removed to access the VCT solenoids. It is best practice to replace the valve cover gasket and spark plug tube seals to prevent oil leaks after the repair.
  Trusted brands: Motorcraft, Fel-Pro
  OEM price range: $40-$70
  Aftermarket price range: $25-$50

Related Codes That Often Appear With This One

• P0014 — This is the same fault ('B' Camshaft Position - Timing Over-Advanced) but for Bank 1. Seeing both P0014 and P0024 simultaneously strongly points to a systemic issue like very dirty/sludgy oil or low oil pressure affecting both banks.
• P0021 — This code is for 'A' (Intake) Camshaft Position - Timing Over-Advanced on Bank 2. If you swap the intake and exhaust solenoids for diagnosis, P0024 may turn into P0021, confirming a bad solenoid.
• P052B — This code indicates Cold Start 'B' Camshaft Position Timing Over-Retarded on Bank 2. Issues within the VCT system can manifest as different timing errors during different engine conditions.
• P0016, P0017, P0018, P0019 — These are camshaft/crankshaft correlation codes. If P0024 is accompanied by one of these, it increases the likelihood of a more serious mechanical timing issue like a stretched timing chain or a failed cam phaser.

Technical Service Bulletins (TSBs) & Recalls

• SSM 54366: Notes P0024 as a potential VCT system DTC and directs to pinpoint tests.
• SSM 47170: States that P0024 may be due to small debris causing the VCT solenoid to stick.
• SSM 50067: Repeats the guidance from SSM 47170, indicating a persistent issue with debris affecting VCT solenoids.
• SSM 49821: Another bulletin covering 2015-2021 vehicles that lists P0024 among a dozen other VCT codes, reinforcing the commonality of this fault across the Ford/Lincoln lineup.

Platform-Specific Known Issues

• TSB SSM 47170 and SSM 50067: These bulletins from Ford state that vehicles may exhibit P0024 (among other VCT codes) due to small debris causing the VCT solenoid to stick. They advise against immediate component replacement without first addressing potential oil contamination issues.

Mechanic-Grade Diagnostic Values

• VCT Solenoid Internal Resistance — expected: 6.9 to 7.9 Ohms is the specific range; other sources give a general range of 5.0 to 14.0 Ohms.. Failure: A reading outside the specified range (especially 0 or infinite Ohms) indicates a faulty solenoid coil.
• VCT Solenoid Connector Voltage — expected: Battery voltage (~12V) on one pin with ignition on, engine off. The other pin is the ground control from the PCM.. Failure: No voltage indicates a wiring issue, blown fuse, or PCM power relay fault.
• Engine Oil Pressure (3.5L EcoBoost) — expected: Minimum of 20 psi at 1500 RPM when at normal operating temperature.. Failure: Pressure below this specification can cause the VCT system to malfunction and set timing codes.
• Live Data: Camshaft Position Variance (Desired vs. Actual) — expected: Should be close to 0 degrees at idle. A variance of less than 3 degrees under load is acceptable after a repair.. Failure: A consistent difference of more than 20 degrees between the desired and actual cam position can trigger the P0024 fault code.

Scan Tool Commands That Help

• Ford IDS / FORScan / Professional Scan Tool: VCT Solenoid Actuator Test (Bidirectional Control) — This command allows you to manually activate the Bank 2 Exhaust VCT solenoid while the engine is running. A functional solenoid and clear oil passages will cause the engine to stumble or stall, confirming the solenoid is mechanically operating. If there is no change in engine operation, the solenoid is stuck or the oil passage is blocked.
• Ford IDS / FORScan / Professional Scan Tool: Monitor VCT PIDs (RCAM, RCAM_DSD, VCT_EXH_ERR) — Monitor the Requested Cam Angle (RCAM_DSD) vs. the Actual Cam Angle (RCAM) and the error PID (VCT_EXH_ERR). This allows you to see the deviation in real-time under different engine loads and pinpoint when the over-advanced condition occurs.

Wiring & Ground Locations

• G104 — On the right-side frame rail, typically located behind the battery.. This is a primary chassis ground point in the engine bay. A poor connection here can cause erratic voltage and sensor readings for various engine components, including the PCM and its sensors.
• G102 / G103 — On the firewall in the engine compartment, near the PCM.. These grounds are critical for the Powertrain Control Module (PCM). A compromised ground at these locations can directly impact the PCM's ability to accurately control the VCT solenoids.
• Cylinder Head to Firewall Ground Strap — Connects from the back of the passenger-side cylinder head to the firewall.. Ensures the engine block and heads have a solid ground reference to the chassis and PCM. An intermittent connection could affect sensor readings that originate from the engine block.
• VCT Solenoid Connector — Front of the Bank 2 (driver's side) valve cover. The exhaust solenoid is typically the lower one or the one closer to the exhaust manifold.. This is the direct connection point for the solenoid. One pin is power (VPWR) and the other is the control signal (ground) from the PCM.

Real Owner Repair Stories

• Ford Truck Enthusiasts Forum (High-mileage (183k miles) 3.5L EcoBoost) — Persistent P0017 (crank/cam correlation, often related to VCT issues)
  ❌ Tried (didn't work) Replacing the VCT solenoids
  ✅ What actually fixed it The final diagnosis pointed to a stretched timing chain or failed cam phaser. However, a critical intermediate diagnostic step was suggested: inspecting the small mesh filter screen located inside the VCT solenoid bore in the cylinder head. On high-mileage engines, this screen can become clogged with sludge, restricting oil flow to the phaser even with a new solenoid.
• YouTube - 3.5L Ford Ecoboost VCT Solenoid failure (2019 Ford F-150 3.5L EcoBoost) — Check Engine Light with codes P0018 and P0021, occasional power loss, and a cold start rattle.
  ❌ Tried (didn't work) Initial diagnosis could have incorrectly pointed to cam phasers due to the rattle.
  ✅ What actually fixed it The diagnostic procedure determined one of the VCT solenoids had failed. Replacing the single bad VCT solenoid resolved all codes and, notably, also eliminated the cold start rattle that is more famously attributed to cam phaser failure.

Model Year Variations Within This Range

• 2018-2021: These models use the second-generation 3.5L EcoBoost. This engine features a more complex dual fuel injection system (port and direct), a revised valvetrain, and a new turbocharger system compared to the 2015-2017 engine. While the VCT system's principle is the same, the surrounding components and engine dynamics are different, and it uses four identical VCT solenoids (Part No. HL3Z-6M280-A).
• 2015-2017: These models use the first-generation 3.5L EcoBoost. This engine is direct-injection only and may use different VCT solenoid part numbers than the later generation. It is known for being harder on engine oil, making clean oil even more critical to prevent VCT issues.