P0024 on 2007-2012 Lexus ES 350: Exhaust Cam Timing Over-Advanced Causes and Fixes

What's Unique About the 2007-2012 Lexus ES 350

The 2GR-FE engine in this Lexus is generally very reliable, but it is sensitive to oil quality and level. The most critical issue for 2007-2008 models is a factory VVT-i oil supply line made with a rubber section that can rupture without warning, causing rapid oil loss and catastrophic engine failure. This part was subject to a recall (Lexus LSC 9LH / Toyota LSC 90K) and any vehicle that has not had the rubber line replaced with the updated all-metal version is a 'ticking time bomb'. While this leak would likely trigger other oil pressure warnings, the resulting loss of oil pressure can also cause VVT system faults like P0024.

Symptoms You May Notice

• Check Engine Light is on
• Rough or unstable idle
• Engine hesitation or stumbling on acceleration
• Reduced engine power
• Decrease in fuel economy
• Engine may be hard to start
• Engine rattling or knocking, especially on cold start (if phaser is failing).

Most Likely Causes

1. Low or Dirty Engine Oil 🔴 High Probability The VVT-i system uses engine oil pressure to actuate the camshaft phasers. If the oil is low, dirty, or the wrong viscosity, it cannot operate the system correctly, often clogging the small passages in the OCV solenoids.
   How to confirm: Check the engine oil dipstick for proper level and inspect the oil's color and consistency. If it is dark, thick, or below the 'add' line, it needs to be changed or topped off.
   Typical fix: Perform an oil and filter change using the manufacturer-specified oil (typically SAE 5W-30).
   Est. part cost: $40-$80
2. Faulty Bank 2 Exhaust Oil Control Valve (OCV/VVT Solenoid) 🔴 High Probability → Shop Engine Variable Valve Timing (VVT) Solenoid These solenoids can become clogged with sludge or fail electrically over time, causing them to stick in one position and prevent proper oil flow.
   How to confirm: The Bank 2 exhaust OCV is on the front-facing cylinder head. A simple test is to swap it with the Bank 1 exhaust OCV (on the rear head). If the trouble code changes to P0014 (the Bank 1 equivalent), the OCV is faulty. You can also test its resistance with a multimeter (should be 6.9-7.9 ohms) or apply 12V to see if the internal plunger clicks.
   Typical fix: Replace the Bank 2 exhaust Oil Control Valve.
   Est. part cost: $40-$120
3. Failing Camshaft Phaser (VVT Actuator) 🟡 Medium Probability → Shop Engine Camshaft The internal locking pin or vanes within the phaser can wear out or get stuck due to oil sludge, preventing it from returning to the default position. A common symptom is a distinct rattling noise from the engine on a cold start. In rare cases on the 2GR-FE, the bolts holding the phaser together can back out, causing a complete loss of timing control and leading to bent valves.
   How to confirm: This is typically diagnosed after confirming the OCV is working correctly. Diagnosis requires a professional-grade scan tool to command and observe phaser angles or physical inspection, which involves removing the valve cover.
   Typical fix: Replace the Bank 2 exhaust camshaft phaser. This is a labor-intensive job that also requires replacing the valve cover gasket.
   Est. part cost: $150-$300

Rare But Worth Checking

• Stretched Timing Chain: → Shop Engine Timing Chain While the 2GR-FE uses a durable timing chain, very high mileage or poor maintenance can cause it to stretch, leading to incorrect timing readings that can trigger this code.
• Clogged OCV Filter: There is a small filter screen for the OCV that can become clogged with debris, restricting oil flow. It can often be removed and cleaned during OCV replacement.

Diagnosis Steps

1. Verify Engine Oil: Check the oil level and condition on the dipstick. If low or dirty, perform an oil change with the correct viscosity oil (SAE 5W-30) and clear the code to see if it returns.
2. Inspect OCV Wiring: Locate the Bank 2 (front) exhaust OCV and inspect its electrical connector and wiring for any damage or corrosion.
3. Test the OCV: Use a scan tool to command the solenoid on and off, listening for a click. Alternatively, remove the solenoid and apply 12V directly to its pins to check for plunger actuation.
4. Swap the OCVs: The easiest confirmation test is to swap the Bank 2 exhaust OCV with the Bank 1 exhaust OCV (on the rear cylinder head). Clear the codes and drive the vehicle. If the code returns as P0014, the OCV you moved is the problem.
5. Inspect OCV Filter: When the OCV is removed, check its small filter screen for sludge or debris and clean or replace as needed.
6. Advanced Diagnosis: If the OCV is confirmed to be good and the problem persists, the issue likely lies with the camshaft phaser or timing chain. This may manifest as a cold-start rattle. Diagnosis typically requires a professional scan tool to monitor commanded vs. actual cam angles or physical inspection of the timing components.

Parts You'll Likely Need

• Engine Oil Control Valve (VVT Solenoid) (OEM #15330-0P020) — This is the most common part to fail for code P0024. It gets stuck or clogged, preventing proper control of the camshaft timing. This part number supersedes the older number 15330-31020.
  Trusted brands: Denso, Aisin, Toyota Genuine
  OEM price range: $90-$150
  Aftermarket price range: $40-$80
• Camshaft Timing Gear Assembly (Exhaust Phaser) (OEM #13080-31020) — If the OCV is not the cause, the mechanical phaser is the next most likely culprit, often due to internal wear or sludge causing it to stick.
  Trusted brands: Toyota Genuine
  OEM price range: $200-$300
  Aftermarket price range: $150-$220

Related Codes That Often Appear With This One

• P0014 — This is the equivalent code for Bank 1 ('B' Camshaft, Bank 1). If you swap the Bank 2 exhaust OCV with the Bank 1 exhaust OCV for diagnosis and this code appears, it confirms the OCV is the faulty part.

Technical Service Bulletins (TSBs) & Recalls

• Lexus Limited Service Campaign (LSC) 9LH - VVT-i Oil Line Replacement for 2007-2008 ES 350.
• Toyota Limited Service Campaign (LSC) 90K - VVT-i Oil Line Replacement, which covered many 2GR-FE powered vehicles.
• T-SB-0094-09 Rev1 - Addresses a ticking noise and VVT-related DTCs (including P0024) on 2005-2009 2GR-FE engines, which may require phaser replacement.

Platform-Specific Known Issues

• A Limited Service Campaign (LSC 9LH for Lexus, LSC 90K for Toyota) was issued for 🎬 See this breakdown of the VVT-i oil line TSB and recall. 2007-2008 ES 350 models for a VVT-i oil line that could rupture. The original part has a rubber hose section, while the updated part is all-metal (Part No. 15772-31030). A rupture causes 🎬 Watch: Step-by-step walkthrough for replacing the VVT-i oil line. catastrophic oil loss and engine seizure, often with little warning. The campaign extension ran until December 31, 2021, so any vehicle that missed the recall should be inspected immediately.

Mechanic-Grade Diagnostic Values

• Oil Control Valve (OCV) resistance — expected: 6.9 to 7.9 Ohms at 68°F (20°C). Failure: A reading outside of this range, or an open/short circuit, indicates a faulty solenoid coil.
• Camshaft Position Sensor Voltage — expected: Typically 0.5V to 4.5V. Failure: A voltage that is consistently high, low, or erratic can indicate a sensor failure.
• Techstream Live Data: Commanded vs. Actual Cam Angle — expected: The actual angle should closely follow the target angle commanded by the ECM.. Failure: A difference of more than 5-10 degrees between the target and actual angle for several seconds can trigger the DTC.

Scan Tool Commands That Help

• Toyota Techstream: Active Test: Control the VVT System (VVT CTRL B2) — This function allows a technician to command the Bank 2 OCV solenoid ON or OFF to verify its operation. This helps determine if the solenoid is physically capable of actuating, isolating a stuck solenoid from a wiring or ECM problem. The engine may run rough or stall during this test.
• Toyota Techstream: Data List: VVT Target Angle vs. VVT Change Angle — This allows for monitoring the ECM's commanded camshaft angle versus the actual angle reported by the camshaft position sensor in real-time. This is critical for diagnosing a lazy or stuck phaser when the OCV itself tests good.

Wiring & Ground Locations

• Bank 2 Exhaust OCV Connector — On the front-facing (Bank 2) cylinder head, connected to the exhaust VVT solenoid.. This is the primary connector to inspect for corrosion, damage, or loose pins when diagnosing P0024. A poor connection here can mimic a failed solenoid.
• Engine Ground Points — Multiple ground points exist. Key grounds for the engine control system are typically located on the cylinder heads, engine block, and chassis near the battery. For example, on a 2008 ES 350, ground point 'A1' is behind the left headlamp assembly.. A poor engine ground can cause a variety of electrical issues, including erratic sensor readings and incorrect actuator operation, potentially leading to VVT-related codes.

Real Owner Repair Stories

• YouTube channel 'speedkar99' (2007 Lexus ES 350 with 213,000 km) — Difficulty starting, running on three cylinders, horrible engine noise.
  ❌ Tried (didn't work) Initial diagnosis pointed towards a timing issue, but the specific cause was internal.
  ✅ What actually fixed it The bolts on the rear bank (Bank 1, but illustrates the failure mode) intake camshaft VVT gear had backed out completely, causing the phaser to lose control, leading to piston-to-valve contact and bent valves. The engine required replacement. This is a catastrophic failure mode that can result from VVT issues.

OEM Part Supersession History

• 15330-31020 → 15330-0P020 — This is a common supersession for Toyota parts, likely indicating a minor revision or change in supplier. The parts are interchangeable.
• VVT-i Oil Line (with rubber section) → 15772-31030 (all-metal) — The original rubber section was prone to rupturing, leading to catastrophic oil loss. The all-metal line is a reliability and safety update.
  Heads up: The old rubber line should never be used as a replacement.

Model Year Variations Within This Range

• 2007-2008: These model years were equipped with the problematic VVT-i oil line containing a rubber section that is prone to rupture. Models from 2009-2012 came from the factory with the updated all-metal line.

Diagnostic Flowchart

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: For this repair, used parts are generally not recommended for the key components. However, if a connector or a section of the wiring harness is damaged, sourcing one from a junkyard vehicle can be a cost-effective and viable repair.

Donor-vehicle mileage cap: roughly under 100000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• For an OCV/solenoid, inspect the screen for metal debris or sludge.
• For a wiring connector, ensure the plastic is not brittle and the locking tab is intact.
• Check the donor vehicle's oil cap and dipstick for signs of heavy sludge, which would indicate poor maintenance and suggest avoiding all engine components from that vehicle.

OEM-only on this vehicle (don't cheap out):

• Camshaft Phaser (VVT Actuator): Due to the complexity and precision required for this part, OEM (Toyota Genuine) is strongly recommended for reliability and to avoid immediate repeat failure.
• Timing Chain: Given the labor-intensive nature of a timing chain replacement, using a high-quality OEM part is critical to ensure longevity.

Aftermarket brands forum-validated for this vehicle:

• Denso: Denso is an original equipment manufacturer (OEM) for Toyota, so their VVT solenoids are considered equivalent to Toyota Genuine parts.
• Aisin: Aisin is another OEM supplier for Toyota and their parts are held in high regard for quality and fitment.
• NTK (NGK): Some users report positive experiences with NTK VVT solenoids, which are from the same parent company as NGK spark plugs.

Brands owners have reported issues with on this vehicle:

• Dorman (for solenoids): While Dorman makes a wide range of parts, their electronic components and solenoids have a mixed reputation. Some users report premature failure compared to OEM or OEM-supplier brands, making the lower cost a poor value if the repair has to be done twice.
• Unbranded/White-Box eBay/Amazon parts: These parts often have questionable quality control and may not perform correctly or fail quickly. It is generally advised to avoid them for critical engine components.

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Related OBD-II Codes

• P0014 — This is the direct equivalent of P0024 but for Bank 1 (the rear cylinder head). It will often appear after swapping a faulty Bank 2 exhaust OCV with the good Bank 1 OCV as a diagnostic confirmation step.
• P0023 — This code indicates an electrical circuit fault (open or short) in the Bank 2 exhaust OCV solenoid. It can appear alongside P0024 if the root cause is damaged wiring or a faulty connector, rather than a mechanical issue with the solenoid.
• P0390 — This code points to a fault in the Bank 2 exhaust camshaft position sensor circuit. It can be triggered with P0024 if there is a wiring harness issue that affects both the sensor and the OCV solenoid, as the ECU relies on the sensor to verify camshaft timing.
• P0021 — This is the timing-over-advanced code for the *intake* camshaft on Bank 2. If the engine oil is extremely low or dirty, it can affect the operation of both the intake and exhaust phasers on the same bank, potentially causing multiple codes.
• P0011 — The equivalent over-advanced code for the Bank 1 intake camshaft. A systemic problem like severe oil sludge or low oil pressure could affect all VVT components and trigger multiple timing codes across both banks.

Frequently Asked Questions