This is one of the most frequent OBD2 trouble codes. Read the full article below to know what it means, how to fix it, and what other codes may show related to it.
Definition
Crankshaft Position/Camshaft Position, Bank 1 Sensor A -Correlation
Meaning
The Camshaft Position Sensor (CMP) determines the position of the camshaft and relays information to the vehicle’s Powertrain Control Module (PCM). The PCM uses data from the CMP to control the fuel injectors for ignition timing to keep cylinders firing efficiently. The Crankshaft Position Sensor (CKP) relays crankshaft position and engine RPM to the PCM or the ignition module. The PCM uses CKP data to control ignition timing and fuel injection. If the sensor signal from either CMP or CKP is faulty or incorrect, the PCM can’t manage engine timing efficiently, causing rough idle or even failure to turn over on startup.
Causes
Computer controlled ignition and fuel injection is a complex and critical process. Sensor failure can lead to a breakdown or even permanent damage if left unchecked. Fixing the problem requires determining the root cause. Here are the common causes of a P00016 trouble code:
- CPM or CKM sensor(s) are faulty
- CPM or CKM open/short circuit
- Timing chain/belt is not calibrated correctly
- Slipped/broken camshaft or crankshaft tone ring.
- VVT system fault
- Faulty PCM
Symptoms
The good news here (if you can call it that) is that the symptoms of a P0016 are obvious. Your check engine light will come on and your engine runs poorly if it will start up. If it won’t start, it usually cranks but won’t turn over.
Diagnosis
Here’s how to troubleshoot a P0016:
Connect your OBD-II scanner here's a great one we use daily - and check the system for other trouble codes. Accompanying codes should help you pinpoint the root cause of the issue. Before you look for any other problems related to the P0016, diagnose and repair any related CPM or CPK trouble codes.
Read the freeze-frame data, paying special attention to the patterns of the camshaft and crankshaft. Take note of the conditions that occur simultaneously with the CPM/CPK codes. Next, clear the codes and test drive your vehicle. If the P00016 code pops up again, keep following the troubleshooting steps.
Can’t find a pattern to the CPM/CKM readings? Check the redactor ring for slipping by checking the alignment. Make sure it’s not loose or damaged, and repair or replace the ring as needed.
Time to Inspect the wiring around the CPM and CKM sensors. Replace frayed or damaged wire and clean or replace the connectors.
After you verify the wiring kit is in good shape, check out the timing belt/chain and all associated components for wear and tear. Pay special attention to your timing chain’s alignment and check for skipped/missing teeth, then repair as needed.
Make a visual inspection of the CPM and CKM for damage. Clean any obstructions with mass air flow sensor cleaner. Also, it never hurts to check if they are installed correctly.
Next, test the camshaft sensor and crankshaft sensor wiring. Unplug the sensor you’re testing, then turn your ignition in accessory mode. Touch the ground with the black lead (like a negative battery terminal) and touch the positive lead to the disconnected sensor leads one at a time. One of the wires should read 1.5 volts if everything is working properly. Any other voltage reading means the sensor is not receiving the necessary voltage. A bad voltage reading means the wiring harness needs to be repaired.
After you do a DC ground check, leave the wires disconnected and switch the multimeter to AC voltage. Connect meter leads to the pins on the CPM and ask an assistant to crank the engine while you watch the read-out. The voltage should pulse on the meter display, but if it doesn’t, the sensor is faulty. Repeat this process for the CKM.
Finally, compare the viscosity of your motor oil with the recommended specifications. If you’re not using the correct oil, do an oil and filter change and use the recommended oil.
Common mistakes
As is often the case, sensors are condemned and replaced without conducting a thorough troubleshooting process. Skipping troubleshooting overlooks the far more common problems behind a P0016 trouble code: disconnected, damaged, burnt or corroded wiring and/or connectors. Seeing a P00016 code can also indicate poor quality workmanship after a recent timing belt or timing chain replacement. If the mechanic didn’t align the crank and camshafts properly, it’s going to cause CPM and CKM errors to pop up soon after.
Checking engine timing should take precedence over sensor or wiring replacement, especially on applications that are fitted with variable valve or camshaft timing. Low oil levels, oil pressure, or failed VVT/VCT solenoids also contribute to P0016, too. Verify everything you can before you start replacing parts to save yourself time and money.
How serious is this?
Code P0016 is a “red alert” OBD-II code. Your vehicle can break down and be completely immobilized if the correlation between the CPK and CPM fails. Worse still, depending on the cause of the breakdown, some engines (interference type engines using timing belts) can suffer severe or fatal damage should they suffer a timing belt break or slippage.
What repairs can fix the code?
- If you find any faulty or damaged wires/components while troubleshooting, repair/replace them, clear the codes and test drive the vehicle. If P0016 recurs, go to the next step.
- Check the timing chain for slipped alignment even if you adjusted it during trouble shooting. The timing chain could be stretched and may need to be replaced along with the timing guides. Once that’s done, see if the P0016 recurs.
- Your next option is to replace the CPM even if it passed the multimeter test. Heat and vibration over time often cause intermittent issues in the camshaft sensor that may not show up when troubleshooting.
- Finally, try replacing the oil control valve for the bank 1 camshaft if your are still seeing the P0016.
Related codes
None listed.
Conclusion
Camshaft and crankshaft issues are serious, and you want to correct them as soon as possible to avoid breakdowns or permanent engine damage. Given the complex nature of realigning components in the timing system, fixing a P0016 isn’t recommended for DIY mechanics.
If you can, take your car into a professional automotive service center and get the problem fixed correctly the first time. You don’t want to end up stranded by the side of the road or have to replace your engine because you missed a step somewhere.
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