P0018 on 2016-2017 Chevrolet Equinox: Crank/Cam Correlation Causes and Fixes

What's Unique About the 2016-2017 Chevrolet EQUINOX

The GM 3.6L V6 (LFX) engine used in the Equinox is notorious for premature timing chain wear and stretching. This issue was so prevalent on earlier versions (LY7, LLT) that GM issued special coverage programs and multiple Technical Service Bulletins (TSBs). While the LFX engine in the 2016-2017 models features an improved chain design compared to pre-2013 versions, it remains susceptible to this failure. A primary contributing factor is the GM Oil Life Monitor (OLM) system, which can recommend oil change intervals as long as 8,000-12,000 miles. Such long intervals, combined with the engine's tendency to consume oil, can lead to low oil levels and degraded oil quality, accelerating wear on the chains, guides, and tensioners.

Diagnostic Flowchart

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

Symptoms You May Notice

• Check Engine Light is on
• Engine rattling or scraping noise, especially on a cold start (often called 'death rattle')
• Rough or unstable idle
• Reduced engine power and poor acceleration
• Engine misfires or hesitation
• Noticeably decreased fuel economy
• In severe cases, the engine may be hard to start or may not start at all

Most Likely Causes

1. Stretched Timing Chains 🔴 High Probability → Shop Engine Timing Chain The 3.6L V6 engine has a well-documented history of premature timing chain stretching due to the original chain design and wear on the chain's internal pins. This is the most common cause for P0018. The issue is exacerbated by extended oil change intervals recommended by the Oil Life Monitor.
   How to confirm: A definitive diagnosis requires physically inspecting the chains for slack after removing the front engine timing cover. A technician can also use a scan tool to monitor camshaft deviation data; a consistent variance greater than 4-5 degrees between desired and actual cam angles points to a timing issue. 🎬 Watch: How to use a labscope to diagnose timing issues.
   Typical fix: Replace all three timing chains (one primary, two secondary), all guides, and all three tensioners using a complete kit. It is highly recommended to replace the water pump (which is driven by the timing chain) and camshaft phasers at the same time.
   Est. part cost: $300-$700 for a complete, high-quality timing chain kit.
2. Failed Timing Chain Tensioner(s) 🔴 High Probability → Shop Engine Timing Chain The hydraulic tensioners rely on clean oil and pressure to keep the chains taut. They can weaken, get stuck, or fail due to wear or oil sludge, leading to a loose chain which then accelerates wear.
   How to confirm: Diagnosed during a physical inspection for a timing chain replacement. A fully extended tensioner piston is a clear sign that the chain has stretched excessively.
   Typical fix: Tensioners are always replaced as part of a complete timing chain service. They are included in all reputable timing chain kits.
   Est. part cost: $50-$150 for a set of tensioners.
3. Low or Degraded Engine Oil 🟡 Medium Probability The entire variable valve timing (VVT) system, including the chain tensioners and cam phasers, is hydraulically operated. Following the factory Oil Life Monitor too strictly or using incorrect oil can lead to sludge and accelerated wear on all timing components. The LFX engine is also known for consuming up to a quart of oil every 2,000 miles, making low oil levels a common problem.
   How to confirm: Check the oil level on the dipstick and inspect its condition. If it's very low, black, or sludgy, this is a likely contributing factor.
   Typical fix: Perform an oil and filter change with the correct viscosity oil (5W-30 dexos-approved). However, if the P0018 code is already present, an oil change alone will not fix a stretched chain.
   Est. part cost: $40-$80
4. Faulty Camshaft Actuator Solenoid (VVT Solenoid) ⚪ Low Probability → Shop Engine Camshaft These solenoids control oil flow to the cam phasers. They can get clogged with debris from dirty oil or fail electrically, causing timing correlation issues. While a possible cause, it's far less common than chain stretch for this specific code.
   How to confirm: A technician can command the solenoid on and off with a scan tool while monitoring cam angle data. Resistance can also be checked with a multimeter. A common diagnostic step is to swap the Bank 2 intake solenoid with the Bank 1 intake solenoid; if the code changes to P0016 (Bank 1), the solenoid is confirmed faulty.
   Typical fix: Replace the Bank 2 intake camshaft actuator solenoid. They are relatively easy to access and replace.
   Est. part cost: $30-$90

Rare But Worth Checking

• Failed Camshaft Phaser: → Shop Engine Camshaft The phaser itself can get stuck or fail to respond to commands from the solenoid, even if the solenoid is good. This is less common than chain stretch but is a possibility. It is typically replaced during a timing chain job.
• Shifted Crankshaft Reluctor Wheel: → Shop Engine Crankshaft As mentioned in TSB #PIP3423P, the reluctor wheel on the crankshaft (which the crank sensor reads) can sometimes move, causing a discrepancy even with a good timing chain. This is a very rare and complex failure.

Diagnosis Steps

1. Verify the engine oil level and condition. If low or dirty, correct this first, clear the codes, and see if the problem returns. Ensure dexos-approved 5W-30 oil is used.
2. Use a professional scan tool to check for any other related DTCs. Codes like P0008, P0009, and P0016 are strong indicators of a timing chain issue.
3. Monitor live data from the camshaft and crankshaft position sensors. Observe the 'Camshaft Position Variance' for Bank 2. A significant, consistent deviation (e.g., > 4-5 degrees at idle) points to a mechanical timing problem.
4. Command the Bank 2 intake VVT solenoid on and off with the scan tool. If the camshaft angle does not change, it could indicate a bad solenoid, a stuck phaser, or an oil pressure problem.
5. As a diagnostic test, swap the Bank 2 intake solenoid with the Bank 1 intake solenoid. Clear codes and drive. If the code returns as P0016, the solenoid is faulty. If P0018 returns, the issue is mechanical.
🎬 See this guide on testing and fixing P0018 correlation codes.
6. If the above steps suggest a mechanical fault, the next step is to remove the engine timing cover for a physical inspection of the timing chains, guides, and tensioners. Check for chain slack and the extension of the tensioner pistons.

Parts You'll Likely Need

• Engine Timing Chain Kit (OEM #ACDelco 12700436 or 12700437 (Verify by VIN)) — This is the most common fix. A complete kit should include all three chains, all guides, and all three tensioners to do the job correctly.
  Trusted brands: ACDelco (OEM), Cloyes
  OEM price range: $400-$700
  Aftermarket price range: $250-$500
🎬 Watch: A complete walkthrough of the timing chain replacement process.
• Camshaft Position Actuator Solenoid (Intake) (OEM #ACDelco 12679099 (supersedes 12655420, 12628347)) — A less common but possible cause. It's often replaced as a preventative measure during a timing chain job, but can be tried as a standalone fix if diagnostic data points to it.
  Trusted brands: ACDelco (OEM), Delphi
  OEM price range: $40-$90
  Aftermarket price range: $25-$60

Related Codes That Often Appear With This One

• P0008 — A general engine position system performance code for Bank 1. It often appears with other timing codes on the 3.6L engine.
• P0009 — The same as P0008, but for Bank 2. Seeing P0008 and P0009 together with P0018 is a classic sign of a major timing chain issue affecting both banks.
• P0016 — This is the identical fault as P0018 (Crank/Cam correlation) but for Bank 1. If both codes are present, it confirms the problem affects the entire engine, pointing strongly to the primary timing chain.
• P0017 — Crank/Cam correlation error for the Bank 1 exhaust camshaft. Often appears with P0016.
• P0019 — Crank/Cam correlation error for the Bank 2 exhaust camshaft. Often appears with P0018.

Technical Service Bulletins (TSBs) & Recalls

• PIP3423P: Diagnostic aid for P0008, P0009, P0016-P0019, points to checking for loose timing chains.
• 12-06-01-009G: Information on updated High Feature V6 timing chain kits and guidance on guide replacement.

Platform-Specific Known Issues

• GM Technical Service Bulletin #PIP3423P directly addresses codes P0016, P0017, P0018, and P0019, instructing technicians to inspect for loose timing chains or tensioners as the primary cause. [⭐ MANUFACTURER TSB — highest authority]
• GM Technical Service Bulletin #12-06-01-009 (with several revisions like F and G) announces the availability of updated timing chain kits to address stretch issues and provides guidance on when to replace guides.
• GM previously had a special coverage program (11340C) that extended the warranty on timing chains for certain 3.6L V6 engines to 10 years/120,000 miles, acknowledging the high failure rate. While likely expired for 2016-2017 models, it confirms the known defect.

Mechanic-Grade Diagnostic Values

• Camshaft Position Actuator Solenoid (VVT Solenoid) Resistance — expected: 5.0 to 15.0 Ohms. Failure: A reading outside this range, especially an open circuit (infinite resistance) or a short (near zero ohms), indicates a failed solenoid.
• Camshaft Position vs. Crankshaft Position Correlation — expected: Bank 2 intake camshaft should be within 6 degrees retarded or 9 degrees advanced of the crankshaft position.. Failure: Exceeding these thresholds will cause the ECM to set DTC P0018.
• Camshaft Position Sensor Signal Circuit Voltage (Key On, Engine Off) — expected: 4.8 to 5.2 Volts. Failure: A reading outside this range indicates a wiring or ECM issue.
• Camshaft Position Sensor Low Reference Circuit to Ground — expected: Less than 5.0 Ohms. Failure: A reading greater than 5.0 Ohms indicates high resistance or an open in the sensor's ground circuit.

Scan Tool Commands That Help

• GDS2 (GM Techline Connect): Camshaft Position Actuator Test — This bidirectional command allows a technician to manually command the Bank 2 intake VVT solenoid on and off while observing the 'Camshaft Position Variance' PID. If the variance does not change when commanded, it points to a faulty solenoid, clogged oil passage, or a stuck phaser. This is a critical step to isolate a solenoid issue from a mechanical timing chain problem.
• GDS2 (GM Techline Connect): Crankshaft Position Variation Learn — This procedure must be performed after replacing the crankshaft, crankshaft position sensor, or the ECM. It compensates for minor variations in the crankshaft reluctor wheel. While not typically required for a P0018 timing chain job, it is a necessary step if the crankshaft or its reluctor wheel is replaced, which is a rare cause of this code.

Wiring & Ground Locations

• Engine Block Grounds — The 3.6L LFX engine has several key ground points. One is on the back of the cylinder head (Bank 2, near firewall) above the thermostat housing. Another major ground from the battery connects to the engine block, sometimes hidden under the lower radiator hose.. A poor ground connection for the ECM or its sensors can cause erratic signals and false codes. Verifying these grounds are clean and tight is a crucial step in any electrical diagnosis.
• ECM Connector X2 — This is one of the main connectors at the Engine Control Module (ECM).. The wiring for the Bank 2 camshaft position sensor runs through this connector. If diagnosing a sensor circuit fault, testing for continuity and voltage would happen at the pins within this connector.

Real Owner Repair Stories

• YouTube channel 'ScannerDanner' (2009 Chevrolet Traverse 3.6L V6 (LFX engine family)) — P0018 code appeared a few months AFTER the owner had already replaced all the timing chains and phasers as preventative maintenance.
  ❌ Tried (didn't work) Replacing the VVT solenoids with new ACDelco parts.
  ✅ What actually fixed it Advanced diagnosis using a PicoScope to compare camshaft and crankshaft waveforms revealed that the new Bank 2 intake camshaft timing was still off by approximately 3 degrees retarded. This indicated a likely error in the installation of the new timing components, proving that even with all new parts, the mechanical timing must be set perfectly. The fix required re-verifying the mechanical timing.
• Reddit user in r/MechanicAdvice (GM 3.6L engine) — Persistent P0017 code (Bank 1 exhaust correlation, a similar mechanical fault) after a timing job.
  ❌ Tried (didn't work) Replacing timing chain, tensioners, and VVT sprockets (phasers)., Testing oil control solenoids, which were confirmed to be working.
  ✅ What actually fixed it The technician discovered the dowel pin on the exhaust camshaft had broken off. This prevented the new phaser from locking into its correct position relative to the camshaft, causing the timing correlation error despite all the new timing components.

When the Usual Fixes Don't Work

• While a complete timing chain kit replacement is the most common and accepted fix, it is not a guaranteed solution if the installation is not performed with absolute precision. As seen in a documented repair on a similar 3.6L engine, a P0018 code can appear after a full timing job if one of the camshafts is off by as little as 3 degrees, requiring a second teardown to verify the mechanical timing marks.

OEM Part Supersession History

• 12578517, 12628347, 12646783, 12655420 → 12679099 — Part consolidation and potential minor internal improvements over the service life of the engine family.
  Heads up: The newest part number, 12679099, is the correct service replacement for the previous numbers on the LFX engine.

Model Year Variations Within This Range

• 2016-2017: The 2016 model year received a cosmetic refresh, but for the 3.6L V6 powertrain, there were no significant mechanical changes affecting the causes or diagnosis of code P0018 within the 2016-2017 model years. Both years use the same LFX V6 engine and timing components.