P0016 Code on a Buick: Crankshaft–Intake Camshaft Position Correlation, Bank 1 (Buick Guide)

P0016 is GM's "Crankshaft Position – Camshaft Position Correlation, Bank 1 Sensor A" — on newer engines GM words it "Crankshaft Position – Intake Camshaft Position Not Plausible." In plain terms, the bank 1 intake camshaft is not where the engine computer expects it relative to the crankshaft. On a Buick that sentence covers very different problems: a stretched timing chain on a 2008–2012 Enclave, a reluctor that has spun on the camshaft of a Regal or Verano 2.4L, a sticking park-lock valve on a 2017–2019 LaCrosse 3.6L, or a stuck solenoid bolt on an Encore GX 1.3T. The surprise is how often the chain is not the answer — GM has written bulletins for Buick engines that set P0016 while the engine is timed correctly.

What Does P0016 Mean on a Buick?

Your Buick's engine computer reads a toothed wheel on the crankshaft and a toothed wheel on each camshaft. Because a chain ties them together, every intake cam pulse should land at a known crankshaft angle. GM's published monitor tables for its 2015 3.6L engines describe the test: P0016 fails when bank 1 intake cam pulses arrive more than about 9 crank degrees early or 12 crank degrees late (a tighter window applies on the dual-idler-sprocket version of the test), two failed tests out of three, and it is a two-trip code.

One detail in GM's tables explains a lot: the test only runs while the cam phaser is "parked." So P0016 measures base mechanical timing — chain, sprockets and reluctor wheels. But if a phaser will not return to park, the cam still reads out of place, which is why a stuck actuator valve can set this "timing" code on an engine whose chain is fine.

"Sensor A" is the intake cam. On a Buick V6, bank 1 is the bank with cylinder 1 — the right bank seen from the flywheel end. In the transverse Enclave, LaCrosse and Regal that is the rear bank, toward the firewall. Four-cylinder Buicks only have bank 1.

Which Buicks Set P0016

The Buick engines GM has written about for P0016:

• 3.6L/3.0L High Feature V6, first generation (LY7, LLT, LF1, LFX): 2008–2017 Enclave, 2005–2016 LaCrosse, 2007 Allure (Canada).
• 3.6L, second generation (LGX, LFY): 2017–2019 LaCrosse, 2018–2020 Regal GS, 2018-on Enclave.
• 2.0L turbo and 2.4L Ecotec (LHU, LAF, LEA, LUK): 2011–2016 Regal, 2010–2016 LaCrosse 2.4L, 2012–2016 Verano.
• 1.3L turbo (L3T): Encore GX.

The fix depends more on which engine you have than on the code. Check the engine RPO code on your vehicle's service parts label.

Enclave and LaCrosse 3.6L: Timing Chain Stretch

On the first-generation 3.6L, P0016 most often arrives with friends: P0008, P0017, P0018 or P0019. That cluster is the classic sign of stretched timing chains, and GM's bulletin 12-06-01-009F names the 2008–2012 Enclave, 2007–2012 LaCrosse and 2007 Allure directly.

The bulletin says something most shops ignore. GM's timing chain kits deliberately leave out the idler sprockets, cam actuator gears, crankshaft gear and guides, and GM states those parts "are being replaced unnecessarily and are not worn." Guides are replaced only when the wear block is worn through into the base material. GM's kits by Buick application:

• 12650230 — 2007 Allure, Enclave and LaCrosse with the LY7.
• 12650231 — 2008 Enclave LY7.
• 12651450 — 2010 LaCrosse LF1, 2010–2011 LaCrosse LLT, 2012 LaCrosse LFX, 2009–2012 Enclave LLT.

The bulletin also adds cam thrust washers on heads built before June 5, 2009, PCV and bank 2 cam cover parts on 2007–2011 Enclaves, and an Oil Life Monitor calibration update. That last item is the root cause in one line: GM linked the chain wear to oil change intervals. GM's Special Coverage 11340C covered timing chains on the 2009 Enclave for 10 years or 120,000 miles; that term has passed for practical purposes, though a dealer VIN check is free.

The job is big. GM's warranty times in 12-06-01-009F are 9.5 hours on a FWD Enclave, 9.7 hours AWD, 9.2 hours on a 2010–2012 LaCrosse and 6.2 hours on a 2007–2008 LaCrosse or Allure. Our Buick LaCrosse and Regal timing chain kit parts guide covers what goes into it.

Before committing, GM's PIP3423 adds a warning for the same engines (it lists the 2007–2016 Enclave and the LaCrosse): if the chains and tensioners are tight and service information finds nothing, the crankshaft reluctor may have moved. A borescope through the crank sensor hole should show 25–26 mm from the machined crank throw to the gap in the reluctor. If it has slipped, the fix is a crankshaft, and a chain kit will not clear the code.

2017–2019 LaCrosse, Regal GS and Newer Enclave

The second-generation 3.6L (LGX in the LaCrosse and Regal GS, LFY in the 2018-on Enclave) has a different P0016 story. GM's PIP5730B covers the 2017–2019 LaCrosse and 2018–2020 Regal with the LGX, and describes P0011, P0016, P0018 or P0021 with usually no drivability complaint.

GM's cause: the intake camshaft position actuator park lock solenoid valves sticking in the actuator, or coming apart with part of the valve stuck inside. GM notes that normal diagnosis does not lead a technician to these valves. The procedure is to remove and inspect them; if only one bank is setting codes and nothing is visibly damaged, swap them bank to bank and see if the code follows. If they are bad, GM says replace both.

A lone P0016 on a 2017–2019 LaCrosse with no rattle and no running complaint deserves a look at those valves before anyone quotes a chain job.

Regal, Verano and LaCrosse 2.0T/2.4L

GM's PIP4548F is titled "MIL On With DTC P0016 And/Or P0017 Setting On A Properly Timed Engine Or Crank No Start." It names the 2011–2016 Regal, 2010–2016 LaCrosse and 2013–2016 Verano with the 2.0L LHU and 2.4L LAF, LEA and LUK. The camshaft reluctor is a press fit with no key; GM says an overheat can let it spin on the camshaft. Spin far enough and the engine will not start. The fix is a camshaft, not a timing chain.

Two more GM documents matter on these engines:

• PIP4716F (2010 LaCrosse 2.4L): a sharp 2–5 second rattle at startup that may set P0011, P0014, P0016 or P0017. GM says check the accessory belt first, then cam actuators that are not parking; if actuators are replaced, inspect the solenoid screens for debris and change the oil, possibly more than once.
• 13-06-01-003H (2010–2013 LaCrosse, 2011–2013 Regal, 2012–2013 Verano 2.4L): GM's oil consumption bulletin. It does not name P0016, but notes the dipstick may show no oil until about 1.25 quarts low — and a 2.4L that runs low starves its phasers.

The 2011 LaCrosse and Regal 2.4L were also part of GM emission recall 11195A, which replaced the camshaft position actuator solenoid valves and reprogrammed the ECM because the solenoids could stick. Ask a dealer to confirm it was completed.

Encore GX 1.3T

GM's bulletin 20-NA-151 covers the 2020 Encore GX (VIN M) with the 1.3L L3T: unstable idle with P0011, P0014, P0016, P0017, P05CC or P05CE. The cause is the camshaft position actuator valve solenoid bolt sticking internally when the oil is hot, and the fix is new intake and exhaust solenoid bolts.

For the 2025 Encore GX, GM's PIP6082 blames surge or misfire with P0016 on debris in the cam actuators. Cam variance should normally be under 3 degrees; if it is erratic, check the oil and filter for metal. If metal is found, both actuators and solenoid bolts are replaced.

Symptoms of P0016 on a Buick

• Check engine light, often with no running complaint at all
• Rattle for the first few seconds after a cold start (chain stretch on the 3.6L, actuators not parking on the 2.4L)
• Rough or unstable idle, especially when hot (Encore GX 1.3T)
• Extended cranking or a crank-no-start (spun cam reluctor on the 2.0T/2.4L)
• P0008, P0017, P0018 or P0019 alongside it on the first-generation 3.6L

Causes and How to Confirm Each

How Is P0016 Diagnosed on a Buick?

1. Identify the engine. The right GM document depends entirely on the RPO code.
2. Record every cam and crank code. A cluster on the first-generation 3.6L points at chains; a lone P0016 needs more proof.
3. Check oil level and condition. On the 2.4L, remember the dipstick can read empty only at about 1.25 quarts low.
4. Read cam/crank variation data with a GM-capable scan tool and compare it to the service limit. On the Encore GX, GM's guide is under 3 degrees of cam variance.
5. Listen at a cold start for a chain or actuator rattle.
6. Check the engine-specific GM item before committing to chains: park lock valves on the LGX, the cam reluctor on the 2.0T/2.4L, the solenoid bolts on the 1.3T.
7. If chains are replaced on a 3.6L, follow 12-06-01-009F — kit only, guides only if worn through — and confirm the Oil Life Monitor update.
8. If the chains are tight and the code persists, check the crank reluctor per PIP3423.

Parts and Cost

GM Documents That Name P0016 on Buick Models

Have a dealer check your VIN against current bulletins and coverages rather than relying on any article, including this one.

What Other P0016 Pages Get Wrong

• "Replace the cam sensor." P0016 is a correlation code. A dead sensor normally sets P0340 or P0341, and GM's P0016 test will not run while those are active.
• "P0016 means timing chain." GM has Buick bulletins for a spun cam reluctor (2.4L), slipped crank reluctor (3.6L), park lock valves (LGX) and solenoid bolts (1.3T) — all setting P0016 with the chain in good shape.
• "Replace every guide and sprocket." GM's 3.6L bulletin says those parts are being replaced unnecessarily.
• Ignoring the oil. GM's chain repair includes an oil life update, and the 2.4L can be well over a quart low before the dipstick shows it.

For other GM brands, see our P0016 Chevy Equinox guide.

Frequently Asked Questions

Is P0016 serious on a Buick Enclave?

It can be. On the first-generation 3.6L it usually means chain wear, which only gets worse. Have the cam/crank variation data checked rather than driving on it indefinitely.

Does P0016 always mean a timing chain on a Buick 3.6L?

No. It is common on 2008–2012 Enclaves and LaCrosses, especially with P0008, P0017, P0018 or P0019. But GM documents a slipped crank reluctor on the same engine, and on the 2017–2019 LaCrosse and Regal GS, sticking intake park lock valves.

Can a Buick Verano or Regal 2.4L set P0016 with good timing?

Yes. GM's PIP4548F covers exactly that: the cam reluctor is a press fit with no key and can spin on the camshaft. The fix is a camshaft.

Is there a GM warranty for Buick timing chains?

Special Coverage 11340C covered the 2009 Enclave for 10 years or 120,000 miles. That term has passed for practical purposes. A dealer VIN check for open campaigns, such as recall 11195A on the 2011 LaCrosse and Regal 2.4L, is free.

What is Sensor A?

On GM dual-overhead-cam engines, Sensor A is the intake cam and Sensor B is the exhaust cam. P0016 is bank 1 intake; P0017 is bank 1 exhaust.

What oil helps prevent P0016?

The dexos-approved grade in your owner's manual, changed on time or sooner and kept at the full mark. GM tied 3.6L chain wear to oil change intervals and documented debris in solenoid screens on the 2.4L.