HINO JO8C Misfire at 1500-2000RPM

[JP910615]

Good evening, im new here. So I have a 1999 Hino Melpha with a J08C engine in it (electronic pump with manual injectors). Bus developed an electrical issue regarding killswitch (bus switched off, killswitch turned off but didnt turn back on when pulled to engage.). Got that issue fixed and then the alternator was overcharging and the check engine light was on. Changed regulator and that fixed the overcharging bit. Check engine light remained on. Bus starts fine during the day and idles, accelerates to about 2,000RPM and then misfires and white smokes heavily. Bus is a little harder to start at night when outside is cooler where you have to give it a couple swings while pressing the accelerator for it to start.

The fault code it reads is a P001D code. Bus can drive, once it starts to misfire, you can change into a higher gear and it drives fine without misfiring until gear develops.

Bus was a little low on fuel when this issue 1st came about. Greasytshirt and Hino123, can you guys help me out?

 

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Engine-Codes - Generic - P001D

P001D Code - 'A' Camshaft Profile Control Circuit/Open Bank 2​

Table of contents
Created and updated by William Orellana on Sep 09, 2024

• Description
• Common Causes
• Symptoms
• How To Fix
• Cost to Fix
• Comments
• Add Comment
• Frequently Asked Questions

Code P001D Description​

The diagnostic trouble code P001D indicates a problem with the 'A' Camshaft Profile Control Circuit/Open in Bank 2 of the engine. This code typically relates to variable valve timing (VVT) systems, which control the opening and closing of the intake and exhaust valves in the engine to optimize performance and fuel efficiency. In this case, the issue is specifically with the camshaft profile control circuit for the 'A' camshaft in the second bank of cylinders.

P001D Code - 'A' Camshaft Profile Control Circuit/Open Bank 2

Common Causes of P001D​

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

1. Faulty Camshaft Position Sensor: A malfunctioning camshaft position sensor can cause the control circuit to open up in bank 2.
2. Wiring Issues: Damaged or corroded wiring in the camshaft profile control circuit can lead to an open circuit and trigger the code.
3. Faulty Camshaft Actuator: A failing camshaft actuator can prevent proper control of the camshaft profile in bank 2.
4. Timing Chain Tensioner Problems: Issues with the timing chain tensioner can affect the camshaft timing and trigger the code.
5. Engine Oil Issues: Low oil levels or dirty oil can impact the VVT system's operation, leading to camshaft control circuit problems.

Symptoms of P001D​

1. Check Engine Light: The most common symptom associated with the P001D code is the illumination of the check engine light on the dashboard.
2. Rough Idle: The engine may run rough or have an irregular idle when this code is present.
3. Decreased Performance: The vehicle may experience a loss of power or reduced acceleration due to timing issues.
4. Engine Misfires: Misfires can occur as a result of the camshaft profile control circuit malfunction, leading to rough running and potential damage to the engine.
5. Poor Fuel Efficiency: The engine may consume more fuel than usual due to the timing issues caused by the code.

How to Fix P001D​

1. Diagnose the Issue: Use a scan tool to retrieve the trouble code and perform further diagnostics to identify the specific cause of the problem.
2. Inspect Camshaft Position Sensor: Check the camshaft position sensor for any signs of damage or malfunction and replace if necessary.
3. Check Wiring: Inspect the wiring in the camshaft profile control circuit for damage, corrosion, or loose connections, and repair or replace as needed.
4. Test Camshaft Actuator: Verify the functionality of the camshaft actuator and replace it if found to be faulty.
5. Address Timing Chain Tensioner: If the timing chain tensioner is causing the issue, replace it to ensure proper camshaft timing.

Cost to Fix P001D​

The cost of repairing the P001D code can vary depending on the specific cause of the issue and the vehicle's make and model. Generally, the parts required for the repair, such as a new camshaft position sensor or camshaft actuator, can range from $50 to $200 each. Labor costs at an auto repair shop can add an additional $100 to $300, depending on the shop's hourly rates and the complexity of the repair. In total, the typical repair cost for this issue can range from $150 to $500 or more. It is essential to consult with a qualified mechanic or repair shop to get an accurate estimate based on your vehicle's needs and location.