When your vehicle’s onboard computer throws a P1390 code, it’s telling you that the timing belt has skipped one or more teeth, throwing off the harmony between the cam sensor and crank sensor.
This misalignment wreaks havoc on engine timing, leading to issues like misfires, poor acceleration, and rough idling. You’re likely wondering what’s behind this problem and how to get your engine running smoothly again.
Let’s take a closer look at the common causes and symptoms of P1390 to get to the bottom of this timing belt trouble.
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Key Takeaways
- The P1390 code indicates a misalignment between the cam sensor and crank sensor, resulting from the timing belt skipping one or more teeth on the timing gears.
- Timing belt wear, improper installation, and crankshaft issues can contribute to this problem, affecting engine performance and potentially causing further damage.
- Symptoms of the P1390 error code include engine hesitation, rough idling, misfires, and the Check Engine Light illuminating.
- Inspecting the timing belt and gears, performing timing maintenance, and verifying engine timing are essential steps to fix the P1390 code.
- Replacing the timing belt, tensioner, and damaged gears and ensuring proper alignment can help resolve the issue and prevent further engine damage.
Code P1390 Description
When your vehicle’s onboard computer detects a misalignment between the cam sensor and crank sensor, it triggers the P1390 code, indicating that the timing belt has skipped one or more teeth on the timing gears.
This misalignment affects the engine’s timing, leading to performance issues like misfires, poor acceleration, and rough idling. Timing belt wear and crankshaft issues can contribute to this problem.
If left unaddressed, it can cause further engine damage. The timing belt plays a vital role in synchronizing the rotation of the crankshaft and camshaft, making it essential to address this issue promptly to maintain engine efficiency and performance.
Common Causes of P1390
The timing belt’s wear and tear over time can cause it to stretch, leading to skipped teeth on the timing gears and triggering the P1390 code.
As you inspect your vehicle, you’ll find that belt wear is a common culprit, causing the teeth to skip and throwing off engine timing.
Improper installation or incorrect tension can also lead to this issue.
Additionally, a seized or failing timing belt tensioner or gear damage can contribute to the problem.
It’s essential to inspect the timing components and sensors to identify the root cause of the P1390 code.
Symptoms of P1390
As you investigate the P1390 code, you’ll likely notice some telltale signs that something’s amiss with your engine’s timing.
One of the most common symptoms is engine hesitation, which can manifest as poor acceleration or misfires. You might also experience rough idling or even engine stalling.
If you’re lucky, the Check Engine Light will illuminate, giving you a heads-up that something’s wrong. Belt failure is a serious issue, and ignoring these symptoms can lead to more severe engine damage.
Pay attention to these warning signs to avoid further complications.
How to Fix P1390
Fixing the P1390 code requires a thorough diagnosis and repair plan to get your engine’s timing back on track.
To address the issue, start by inspecting the timing belt and gears visually for signs of wear, damage, or misalignment.
- Perform a belt inspection to identify any cracks, frays, or excessive wear.
- Conduct timing maintenance by checking the tensioner and adjusting it according to the manufacturer’s specifications.
- Verify the engine’s timing is properly synchronized by consulting your vehicle’s repair manual.
Timing Belt Replacement and Alignment
You’ll need to replace the timing belt, tensioner, and any damaged gears to get your engine’s timing back in sync.
Inspect the belt for wear patterns, such as cracks, frays, or excessive wear on the teeth. This will help you determine the extent of the damage and verify you replace the correct components.
During replacement, pay attention to tensioner maintenance, as improper tension can cause the new belt to skip teeth again. Follow the manufacturer’s specifications for tension and alignment to guarantee a smooth installation.
Proper alignment is vital to prevent further damage and verify your engine runs efficiently.
Engine Timing Adjustment and Testing
With the new timing belt and tensioner in place, it’s time to adjust the engine’s timing to guarantee proper synchronization.
You’ll need to certify the crankshaft and camshaft are correctly aligned to prevent further engine damage.
To do this, you’ll need to perform a timing analysis, which involves:
- Checking the timing marks on the crankshaft and camshaft to verify they’re aligned.
- Using a scan tool to monitor the engine’s timing and identify any issues.
- Adjusting the engine’s timing according to the manufacturer’s specifications to achieve proper synchronization.
After adjustment, perform engine testing to verify the repair and confirm the engine is running smoothly.
Cost to Fix P1390 and Additional Information
The cost of repairing a skipped timing belt can vary significantly, depending on the make and model of your vehicle, as well as the extent of the damage.
On average, the cost of replacing a timing belt, tensioner, and related components can range from $500 to $1000 or more. Labor costs can vary between $80 and $150 per hour.
It’s recommended that you consult with a professional mechanic for an accurate estimate. A thorough timing belt inspection and engine diagnosis will help identify the root cause of the issue, ensuring a proper fix and preventing further engine damage.
Understanding the Powertrain Control Module (PCM)
As the brain of your vehicle’s engine management system, the Powertrain Control Module (PCM) plays a vital role in detecting and responding to issues like the P1390 code.
The PCM processes data from various sensors to guarantee peak engine performance.
- Sensor Functionality: The PCM receives input from sensors like the cam sensor and crank sensor to monitor engine timing and performance.
- Module Calibration: The PCM is calibrated to recognize normal engine operating parameters, allowing it to detect deviations like the P1390 code.
- Error Detection: When the PCM detects a misalignment between the cam sensor and crank sensor, it triggers the P1390 code, alerting you to the issue.
More OBD-II Codes
| P1396 | P1371 | P1370 | P1368 |
| P1367 | P1366 | P1365 | P1364 |
| P1363 | P1360 | P1359 | P1353 |
| P1324 | P1323 | P1322 | P1321 |
| P1320 | P1398 | P1315 | P1399 |
| P1405 | P1406 | P1407 | P1408 |
Frequently Asked Questions
Can a Skipped Timing Belt Cause Engine Failure?
You’ll want to know that a skipped timing belt can indeed cause engine failure, as belt slippage leads to engine stalling, misfires, and poor performance, ultimately resulting in costly repairs or even complete engine failure if left unaddressed.
Will a Timing Belt Replacement Fix Other Engine Issues?
You’re wondering if replacing the timing belt will fix other engine issues. Generally, it won’t address unrelated problems like oil leaks or fuel efficiency concerns, but it will prevent further damage and misfires caused by the skipped belt.
Do All Vehicles Have a Timing Belt?
You’re wondering if all vehicles have a timing belt. Not necessarily; some vehicle types, like those with diesel engines or newer models, use timing chains instead. Belt materials, such as rubber or fiber-reinforced, vary across manufacturers, but not all vehicles rely on belts.
Is It Safe to Drive With a P1390 Code?
Are you playing Russian roulette with your engine’s health? It’s not safe to drive with a skipped timing belt, as it can cause misfires, poor acceleration, and stalling in Drive mode, further damaging your engine due to loose Belt tension.
Can I Replace the Timing Belt Myself?
You can attempt to replace the timing belt yourself, but be prepared for DIY challenges. First, perform a thorough belt inspection to identify worn or damaged components, ensuring you have the necessary tools and technical expertise for a precise replacement.
Conclusion
As you wrap up the repair, bear in mind that prompt attention to the P1390 code is pivotal in preventing precarious performance pitfalls. Precision timing belt replacements and precise engine timing adjustments are key to preventing perpetual problems. Perilous procrastination can lead to pricey repairs, so prioritize proactive maintenance to preserve your engine’s pristine performance.
