You start the car and it struggles to turn over, as if it needs a moment to think. Once running, it feels rough and lacks power. You connect your scanner and see P0016. A bit daunting: this sounds more technical than the average fault code. Still, start cheap. Often it’s a dirty valve or low oil, and only in the worst case is it the timing chain.
Quick answer: Fault code P0016 means the crankshaft and camshaft are no longer synchronized, measured on bank 1 intake side. The computer sees that both sensors don’t have the expected ratio, indicating a timing or VVT problem. The most common cause is a dirty VVT valve or low oil level. Drive carefully and check this quickly, because a truly jumped chain can cause engine damage.
What does fault code P0016 mean?
Your engine has a crankshaft that drives the pistons and a camshaft that opens the valves. These two must run precisely in sync. Sensors on both shafts report their position to the computer. If the ratio doesn’t match what’s expected, the computer logs P0016. It’s about the correlation between the crankshaft and camshaft on bank 1, intake side. Variable valve timing (VVT) often plays a role here.
Severity: orange to red. Sometimes the car starts hard or runs poorly, but it’s not too bad. However, a truly jumped timing chain can cause engine damage. Take this code seriously and don’t keep driving stubbornly if the engine sounds suspicious.
Symptoms
Hard starting. The engine cranks slowly or keeps turning over before it starts.
Rough running and power loss. The engine runs unevenly and accelerates less smoothly.
Rattling noise at startup. Sometimes a rattling noise on cold start, plus the engine warning light.
Possible causes (from cheap to expensive)
Dirty VVT valve or low oil level (€0 to €150). A sticking camshaft adjuster valve or insufficient oil disrupts valve timing. Start here, it’s the cheapest fix.
Defective crankshaft or camshaft position sensor (€30 to €150). A sensor that measures incorrectly or not at all gives a wrong ratio.
Stretched timing chain or jumped tooth (€200 to €1200). The chain is stretched or a tooth has shifted, causing the timing to really slip.
Incorrectly installed timing (variable). After a timing job, the timing is sometimes set slightly wrong, resulting in this code.
Step-by-step plan: how to find the cause yourself
- Read both signals live. Connect a scanner and view the crankshaft and camshaft signals live. Note if P0011, P0340, or P0335 also appear.
- Check the oil level first. Too little or old oil disrupts the VVT adjustment. Top up or change if the level is low or the oil is dirty.
- Check the VVT valve. The camshaft adjuster valve can be dirty or sticking. Clean or test it before looking further.
- Measure the sensors. Test the crankshaft and camshaft position sensors and their wiring. A faulty sensor is a relatively cheap fix.
- Compare the timing marks. If the engine runs suspiciously, mechanically compare the timing marks of the crankshaft and camshaft.
- Does everything point to the chain? If the timing chain seems to be the culprit, go to a garage before driving further. Otherwise, you risk engine damage.
How much does it cost?
Yourself: top up oil or clean VVT valve. €0 to €50. The cheapest and often sufficient first step.
Yourself: replace sensor or VVT valve. €30 to €150 for parts.
Garage: replace timing chain. €400 to €1200, including labor and tensioners.
Fix it yourself or go to the garage?
Checking the oil level, cleaning the VVT valve, and replacing a sensor can be done quite easily yourself with some skill. If the signals and markings indicate a stretched or jumped timing chain, then it stops here. That is precise work that can go wrong and cause expensive engine damage. The beauty of P0016 is that you start cheap and only scale up if really necessary.
The right tool for this code
For P0016 you want three things: to read and clear the code, to view the crankshaft and camshaft signals live, and if necessary test sensors and actuators. These three fit that. Start cheap; use the more advanced scanner only if you need deeper measurements.
View the Topdon CarPal →
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View the Launch CRP919X →Related fault codes
P0016 belongs to a family of timing and sensor codes. If you encounter one of these, the approach is similar: P0011 (VVT timing intake side), P0017 (crankshaft/camshaft correlation exhaust side), P0340 (camshaft sensor problem), and P0335 (crankshaft sensor problem). If you don’t yet know how to read and clear codes, first read reading and clearing fault codes.
Frequently Asked Questions
Can I keep driving with P0016?
Short trips are often still possible, but be careful. If the engine sounds rough or rattling, it could be the timing chain. Don’t keep driving and have it checked to prevent engine damage.
Is P0016 always the timing chain?
No. Often it’s a dirty VVT valve, low oil level, or a faulty sensor. The chain is one of the more expensive possibilities, not the first you check.
Can too little oil cause this code?
Yes. The VVT adjustment works on oil pressure. Too low or dirty oil level disrupts valve timing and can cause P0016. So check the oil level first.
Does P0016 go away on its own?
Sometimes it disappears when you fix the cause and clear the code. If it returns after a few drives, the problem is still there and you need to investigate further.
In short
• P0016 = crankshaft and camshaft are not synchronized (bank 1, intake side).
• Start cheap: check the oil level and the VVT valve, and measure the sensors.
• If that doesn’t solve it: compare the timing marks mechanically.
• Everything points to the timing chain: go to the garage before driving further.