P0012: Intake Camshaft Position Timing Over-Retarded (Bank 1)
Can you still drive? Yes, but performance will be reduced. Check oil level immediately and change oil if overdue.
What Does P0012 Mean?
Code P0012 indicates that the intake camshaft on bank 1 is more retarded (delayed) than the ECM has commanded. This is the opposite of P0011. Retarded timing reduces engine performance at higher RPMs and can cause rough running. The issue often relates to oil flow problems preventing the VVT actuator from properly advancing timing.
Need to read your codes?
An OBD-II scanner lets you read and clear diagnostic trouble codes from your vehicle's computer. Most scanners work with any car made after 1996.
Browse OBD-II Scanners on AmazonCommon Causes
- Low engine oil level
- Faulty VVT solenoid stuck in retard position
- Clogged oil control valve
- Worn timing chain causing slack
- Dirty engine oil restricting oil flow
Symptoms
- Check engine light on
- Reduced engine power at higher RPMs
- Poor acceleration
- Increased fuel consumption
- Rough idle
Diagnostic Steps
- 1Check engine oil level and quality
- 2Monitor VVT actuator position with scan tool
- 3Test VVT solenoid by commanding advance
- 4Check oil pressure with mechanical gauge
- 5Inspect timing chain for excessive slack
- 6Clean or replace VVT solenoid
Recommended Parts & Tools
Estimated Repair Cost
| Type | Estimated Cost |
|---|---|
| Total Repair Cost Range | $50 - $1800 |
Get a Personalized AI Diagnostic Report
Get a detailed AI diagnosis for code P0012 specific to your vehicle. Includes step-by-step repair instructions, exact parts needed, and a cost breakdown tailored to your make and model.
Chat with AI About P0012Commonly Affected Vehicles
Related Recalls
1 Active Recall — 2026 Toyota Corolla
The following NHTSA safety recalls have been issued for this vehicle. Contact your dealer to check if your vehicle is affected.
EXTERIOR LIGHTING:HEADLIGHTS
Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain 2026 Corolla vehicles. The front headlights may have missing headlight aim markings, which can result in improperly aimed headlights during service. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 108, "Lamps, Reflective Devices, and Associated Equipment."
Remedy: Dealers will replace both front headlight assemblies, free of charge. Owner notification letters are expected to be mailed April 12, 2026. Owners may contact Toyota's customer service at 1-800-331-4331. Toyota's number for this recall is 26TA05.
Data provided by the National Highway Traffic Safety Administration (NHTSA).
Frequently Asked Questions
What does over-retarded camshaft timing mean?
Over-retarded means the intake camshaft is opening later than the ECM has commanded. This reduces high-RPM performance and can cause rough idling.
Is P0012 expensive to fix?
It depends on the cause. An oil change or VVT solenoid replacement is relatively inexpensive ($50-$300), but a timing chain replacement can cost $1,000-$2,000.
Community Fix Reports
Community reports are user-submitted and not verified by Auto AI Buddy. Results may vary.
Related Codes
Affiliate Disclosure: This page contains affiliate links. If you purchase products through these links, we may earn a small commission at no additional cost to you. This helps us maintain this free resource. We only recommend products we believe will help you diagnose and repair your vehicle. Prices shown are estimates and may vary.