P0012 Error Code: Meaning, Causes, Symptoms, and Fixes

Check engine lights always illuminate on the dashboard whenever there’s an engine malfunction. However, if you see a check engine light accompanied by a poor idling and hard starting, there’s likely a malfunction on the camshaft angle or position. Run a scan check on the vehicle – if it pulls out diagnostic trouble code P0012, follow this article religiously.

This article discusses the meaning, symptoms, causes, diagnostic mistakes, and diagnosis and fix.

Code P0012 Definition

  • P0012 Generic: Camshaft Position Intake—Timing Over-Retarded (Bank 1)
  • P0012 Mazda: CMP Timing Over Retard Right Side
  • P0012 Toyota: ‘A’ Camshaft Position Intake Timing Over-Retarded Bank 1
  • P0012 BMW: Intake Camshaft Position Timing Over-Retarded Bank 1
  • P0012 Ford: ‘A’ Variable Camshaft Timing Over Retarded Bank 1


What Does P0012 Mean?

P0012 is a generic fault code that shows the intake camshaft timing on bank 1 is more retarded than what the powertrain control module [PCM] has commanded it to be.

P0012 in Mazda means an over retarded timing. The variable valve timing on the intake camshaft is not adjusting correctly, making the onboard computer register a fault code.

Toyota P0012 means ‘A’ variable valve timing in the camshaft timing is retarded or advanced.

P0012 BMW means a malfunction on the intake camshaft controlled by VANOS.

Ford P0012 shows an over retarded camshaft timing in the engine.

The ‘A’ in the definition means intake in a straight head cylinder or inline engine.

The ‘Bank 1’ refers to the side of the cylinder head that houses no.1 spark plugs. This applies to V-type or boxer engines.

What Are the Symptoms of Code P0012?

Here are notable P0012 symptoms that you should watch out for;

  • High fuel consumption
  • Engine stalling and hesitation
  • Rough idling
  • Hard engine starting
  • Illuminated check engine light
  • Rattling noise from the engine.

If you notice any of the outlined symptoms above and your scan tool pulls the P0012 fault code, visit a certified mechanic to track down the cause and fix it as soon as possible.

What Cause of Code P0012?

What can cause a P0012 code? The potential causes include the following;

  • Low oil pressure
  • Engine sludge
  • Dirty engine oil because of long oil change interval
  • Low engine oil
  • Lousy oil control valve [OCV]
  • Faulty intake valve control solenoid
  • Bad camshaft timing
  • Short in oil control circuit/ intake timing control

How Serious Is Code P0012?

Diagnostic trouble code [DTC] P0012 affects the vehicle’s drivability. The potential problems are rattling noise from the engine, increased engine hesitation, stalling, rough idling, poor acceleration, and bad gas mileage. If you ignore these signs and continue to drive the vehicle, there will be severe damages to multiple internal engine components.

Code P0012 Common Diagnosis Mistakes

Follow the outlined guides below to avoid common diagnosis mistakes;

  • Always verify the cause of the problem before doing any repair.
  • examine the wiring harness and connections before changing any components.
  • Stick to pinpoint diagnostic instructions to avoid misdiagnoses.
  • Replace only fault components directed by a pinpoint diagnostic test or visual inspection.
  • Check engine oil level via the dipstick. Before replacing any components, find out if you need to change oil and filter or top the oil level to the manufacturer’s specified mark.

Tools Needed to Diagnose Code P0012

These are the tools needed to diagnose and repair error code P0012;

  • OBD II scan tool
  • Oil pressure gauge
  • Fused jumper wire
  • Proper hand tools.

How to Diagnose and Repair Code P0012

How do I fix code P0012 and enjoy a seamless driving experience? Follow the below instructions.

Scan the vehicle and see if any code accompanies the fault code P0012 and erase the engine warning light with an OBD II scan tool.

Check the state of the engine oil. If the oil is low, adjust it to the standard level and test if the problem is resolved. If it’s dirty, change the motor oil and filter and test drive to see if it will solve the problem.

Unbolt the valve cover and remove it to see if there’s sludge buildup. If there’s engine sludge formation, it may block the oil galleries and cause low oil pressure. You’ll need to flush the engine and change the oil and oil filter.

If the engine is clean, inspect the bank 1 intake camshaft oil control valve for optimum operation. To do this, unbolt the [OCV] and supply electric power and grounding to it via a fused jumper wire. If the oil control valve is functioning well, it’ll make a click sound or move based on the specific design. If there’s no click and movement, the valve is bad. Consider replacing it and test drive the vehicle to see if the problem has been resolved.

If the above tests show the components are in good condition, check the oil pressure. Carry out this test when the vehicle runs at an average operating temperature. If there’s low engine oil pressure, there’s likely a malfunctioning oil pressure regulator, bad oil pump, or the engine itself. Suppose the oil pressure is okay; you have timing issues that need a professional diagnosis and fix. Visit a certified auto center.

Same Problems with different Error Code

You can pull out the below codes when a vehicle engine suffers the same problem with P0012 error codes.

p0012 symptoms


Q: Can I drive with a P0012 code?

While driving with P0012 fault code will not keep you on the road, do not continue driving with it. However, since camshaft timing plays a critical role in the overall engine operation, you’ll experience rougher idling, poor acceleration, stalling, hesitation, increased gas consumption, and rattling noise from the engine.

Q: Can low oil cause P0012?

A vehicle engine oil should be at the manufacturer’s specification at all times. The camshaft variable valve timing systems work with adequate oil levels and pressure. If the engine oil goes below the specification, it can cause P0012 errors and multiple error codes.

Wrong oil viscosity can also trigger error code P0012. For instance, if the engine oil is too thick, it’ll not permit the camshaft timing control valve to function as it should, which will cause system malfunctions.

Q: How much does it cost to fix the P0012 code?

Since several factors can trigger diagnostic trouble code P0012, the repair cause will vary based on the actual cause of the problem. If dirty or wrong engine oil is the cause, it will only cost around $50 to fix it. If the reason is engine sludge, then you should budget to spend about $150 to $300. The latter cost may hike up to $500 if the sludge is too much and requires the mechanic to drop the engine for thorough flushing.

Q: What is a camshaft position timing over-Retarded Bank 1?

This bunch of words means a malfunction in the camshaft timing. Let’s break it down.

Camshaft position timing over-retarded Bank 1 means the car computer had detected that the camshaft timing in the Bank 1 cylinder is set before or is retarded than the ECM desired it to be.

Last words

Now, we have learned that a vehicle’s onboard computer registers a fault code whenever it detects a malfunction in the system unit. And the fault code P0012 logs on whenever the computer detects over-retarded intake camshaft timing in Bank 1. The ECM can register the P0012 error code for several reasons.

And in this article, we’ve outlined the causes, symptoms, diagnosis mistakes, and how to diagnose and fix them. So, you are prepared to face the challenge thrown by the said error code. 

Whatever the cause may be, follow the guides above to track down the culprit and fix it. However, if you don’t trust your guts, seek professional help.

Osuagwu Solomon

Osuagwu Solomon is a certified mechanic with over a decade of experience in the mechanic garage, and he has over five years of experience in the writing industry. He started writing automotive articles to share his garage experience with car enthusiasts and armature mechanics. If he is not in the garage fixing challenging mechanical problems, he is writing automotive repair guides, buyer’s guides, and car and tools comparisons.

Leave a Reply

Your email address will not be published. Required fields are marked *

Recent Posts