P0018 on Buick
Crankshaft/Camshaft Position Correlation - Bank 2 Sensor A
P0018 on Buick vehicles indicates crankshaft/camshaft position correlation - bank 2 sensor a. Au7o has documented this code across 2 Buick models — most commonly on Enclave, LaCrosse. This code means the computer detected that the crankshaft and the Bank 2 'A' (typically intake) camshaft are out of their expected timing relationship. The computer compares the crankshaft and camshaft position sensor signals; they should stay in a fixed correlation as the engine turns. When the Bank 2 camshaft is too far off from the crankshaft, P0018 sets, indicating the valve timing on that bank is misaligned. This can cause rough running, reduced power, hard starting, or a no-start, and in some cases signals timing chain or phaser trouble that warrants prompt attention. Typical repair costs on Buick range from $1,500 to $6,500, depending on the specific model and root cause.
Common Causes of P0018
- •Stretched, worn, or jumped timing chain (Bank 2)
- •Worn or broken timing chain guides/tensioner
- •Stuck variable valve timing solenoid or phaser
- •Low or dirty engine oil affecting the phaser
- •Faulty crankshaft or camshaft position sensor
- •Damaged reluctor/tone ring
- •Incorrect timing from prior service
- •Wiring or connector fault at a cam/crank sensor
P0018 on Buick by Model
Buick Enclave(2 issues)
- Enclave 3.6L LLT Timing Chain Stretch + Oil Consumption2008-2012
Early Enclaves (2008-2012, plus shared Traverse/Acadia/Outlook) with the 3.6L LLT direct-injection V6 share LaCrosse's timing chain stretch and a separate excessive-oil-consumption issue. The PCV system pulls oil into the intake, intake valves carbon up (no port injection to wash them), and the chain wears prematurely from stretched OLM intervals.
- Stretched/Worn Timing Chain on 3.6L V62008-2013
The 3.6L (and 2.8L) high-feature V6 in 2008-2013 Enclaves is prone to timing chain stretch and worn chain guides/tensioners, sometimes appearing as early as 40,000-60,000 miles. As the chain elongates, valve timing drifts, triggering misfires and a rattle at idle/startup; if a chain jumps a tooth it can bend valves and cause catastrophic engine damage. GM acknowledged the defect (occurring even with regular oil changes) and issued Special Coverage Adjustment #11340C extending the chain warranty to 10 years/120,000 miles on affected engines.
Buick LaCrosse(2 issues)
- LaCrosse 3.6L LLT/LFX Timing Chain Stretch2010-2016
The GM 3.6L LLT (2007-2011) and LFX (2012+) "High Feature" V6 in LaCrosse, Enclave, Acadia, Traverse, CTS, Cadillac SRX, and many others suffers timing chain stretch typically between 80,000-150,000 miles. Root cause is oil-related — original OLM intervals (up to 12,000 miles) starved the chain of fresh oil. Excessive oil consumption (LLT also has a known consumption issue) accelerates wear.
- 3.6L V6 Timing Chain Stretch and Wear2010-2012
The GM 3.6L V6 (LY7/LLT, and to a lesser extent the early LFX) used in the second-generation LaCrosse is prone to premature timing chain wear and stretch, especially on pre-2012 engines. Worn chains throw off cam-to-crank correlation, setting timing codes and, if neglected, can cause valve-to-piston contact and catastrophic engine damage. The problem is worsened by extended oil-change intervals and a marginal PCV system that accelerates oil contamination.
Looking for P0018 on a different make?
View P0018 across all makes →Frequently Asked Questions
What does P0018 mean on Buick?▼
P0018 stands for "Crankshaft/Camshaft Position Correlation - Bank 2 Sensor A." This code means the computer detected that the crankshaft and the Bank 2 'A' (typically intake) camshaft are out of their expected timing relationship. The computer compares the crankshaft and camshaft position sensor signals; they should stay in a fixed correlation as the engine turns. When the Bank 2 camshaft is too far off from the crankshaft, P0018 sets, indicating the valve timing on that bank is misaligned. This can cause rough running, reduced power, hard starting, or a no-start, and in some cases signals timing chain or phaser trouble that warrants prompt attention. On Buick specifically, this code is documented across 2 models.
What causes P0018 on Buick vehicles?▼
Common causes on Buick: Stretched, worn, or jumped timing chain (Bank 2), Worn or broken timing chain guides/tensioner, Stuck variable valve timing solenoid or phaser, Low or dirty engine oil affecting the phaser, Faulty crankshaft or camshaft position sensor. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0018 on a Buick?▼
Repair costs on Buick range from $1,500 to $6,500, depending on the specific model and root cause.
Which Buick models have P0018 documented?▼
Au7o has documented P0018 on 2 Buick models: Enclave, LaCrosse.