P0021 means the variable valve timing (VVT) system has advanced the camshaft timing on Bank 2 further than the engine control module commanded, and it’s the exact Bank 2 counterpart to P0011, which covers the identical fault on Bank 1. This code only applies to V-configuration engines (V6, V8, and similar layouts) that have two separate cylinder banks each with their own camshaft timing control — an inline engine has only one bank and would never produce a Bank 2 code at all.
What Does P0021 Mean?
Variable valve timing systems use oil pressure, directed through a solenoid, to rotate the camshaft slightly relative to the crankshaft, optimizing performance and efficiency across different RPM ranges. The control module commands a specific target position and monitors an actual-position sensor to confirm the system is tracking correctly. P0021 fires when Bank 2’s camshaft ends up more advanced than commanded — see our P0011 guide for the Bank 1 version of this exact same fault, since the diagnostic approach and causes are nearly identical, just applied to the other bank.
Common Symptoms
- Check engine light on
- A rough or unstable idle
- Reduced power, particularly noticeable under acceleration
- A rattling or ticking noise from the timing chain area — see our engine ticking noise guide
- Reduced fuel economy
Common Causes, Most Likely First
- Low engine oil level or badly degraded oil on Bank 2 specifically — VVT systems rely on adequate oil pressure and clean oil flow to function correctly, and this is the most common, cheapest-to-fix cause. See our how to check engine oil level guide.
- A clogged VVT solenoid screen or filter on Bank 2, restricting oil flow to that specific camshaft actuator even though oil level and condition are otherwise fine.
- A failing VVT solenoid on Bank 2, unable to properly regulate oil flow to hold the commanded timing position.
- Excess timing chain slack from a worn chain, tensioner, or guides on that bank, physically allowing more advance than the system intends.
- A wiring or connector fault affecting the Bank 2 solenoid or its position sensor.
How to Diagnose It
- Check oil level and condition first — see our oil change interval guide if it’s overdue, since old or low oil is the most common root cause across the whole VVT fault family.
- Confirm which bank is actually Bank 2 on your specific engine, since manufacturer conventions vary — your repair manual or a parts-store lookup for your VIN will clarify this.
- Check for an accompanying timing chain noise — see our engine ticking noise guide — which would point toward chain wear rather than a purely oil-flow-related cause.
- Have the VVT solenoid on Bank 2 tested or inspected for debris or failure once oil condition is ruled out.
Never work under a vehicle supported only by a jack. Use axle stands on firm, level ground, chock the wheels that stay down, and leave the car in gear or Park with the handbrake on. A jack lifts; stands hold.
Possible Fixes
| Cause | Fix | Typical cost |
|---|---|---|
| Low/degraded oil | Oil and filter change | $40 – $100 |
| Clogged VVT solenoid screen | Clean or replace the solenoid | $100 – $300 |
| Failing VVT solenoid | Replace the solenoid | $150 – $350 |
| Worn timing chain/guides | Timing chain replacement | $400 – $600+ |
Can I Keep Driving With This?
Yes, in the short term, particularly if the only symptom is the check engine light with no unusual noise — but don’t ignore it indefinitely. If you hear a rattling noise from the engine alongside this code, treat that combination more seriously, since it can indicate timing chain wear that progressively worsens. See our engine ticking noise guide for more on that specific warning sign.
When to See a Mechanic
Reasonably soon — start by checking oil level and condition yourself, since that resolves a meaningful share of VVT-related codes at minimal cost. Get it looked at sooner if you also hear a new rattling or ticking noise. More in our engine section.
Frequently Asked Questions
What does P0021 mean?
It means the variable valve timing system on Bank 2 has advanced the camshaft timing further than commanded — the exact same fault as P0011, just on the other cylinder bank of a V-configuration engine.
What’s the difference between P0021 and P0011?
They’re the same fault on different cylinder banks — P0011 is Bank 1, P0021 is Bank 2. Only V-configuration engines (V6, V8, etc.) with two separate banks can produce both codes.
Can low oil really cause a camshaft timing code?
Yes — variable valve timing systems depend on adequate oil pressure and clean flow to control camshaft position accurately, making low or degraded oil the most common cause of this code.
Is it safe to drive with a P0021 code?
Yes, in the short term, especially if there’s no unusual noise — but get it checked reasonably soon, and treat it more urgently if you also hear a rattling or ticking noise from the engine.
How much does it cost to fix P0021?
Often $40–$100 if it’s simply an overdue oil change, up to $350 for a VVT solenoid, or $400+ if timing chain wear is the underlying cause.
