Misfire and codes P0300, P0301, P0302, P0303, P0304 and P0305

Hi,

The codes are very specific. However, you should feel the misfire. I need to know if the check engine light blinks when the engine is running. If it does, then it's a type one which means it can cause damage to the catalytic converter and it can be ignition related or fuel related. If it stays on, then it's a type two that is likely related to an emission related issue.

If you have a live data scan tool, let me know the short term fuel trims.

Let me know. Also, let me know if the crankshaft position sensor has been replaced.

Take care,
Joe

Have you tired clearing the codes? this video should help us:

https://youtu.be/ahK_eucFi-k

Please run down these guides and report back. Can you please shoot a quick video with your phone of the engine running so we can see what's going on? that would be great. You can upload it here with your response.

Hi,

We are thinking electrical, but there are other things that can cause a misfire. Does the check engine light ever flash? Do you ever feel a rough idle or anything related to the misfire? Have you checked to make sure the fuel pressure is within the manufacturer's specs? Have you checked for engine vacuum leaks?

Here are a couple of links you may find helpful. Check to see if there are any vacuum leaks. If none are found, check to see if the fuel pressure is within spec. Also, let us know if there is a loss of power that could indicate an issue with the catalytic converter.

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Also, if it is possible for you to get the short term fuel trims? that would be helpful.

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Here are the directions specific to your vehicle for testing fuel pressure. The attached pic correlates with the directions and the manufacturer's specifications are included in the directions.

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2010 Acura Truck MDX V6-3.7L
Fuel Pressure Test
Vehicle Powertrain Management Fuel Delivery and Air Induction Fuel Pump Testing and Inspection Component Tests and General Diagnostics Fuel Pressure Test
FUEL PRESSURE TEST
Fuel Pressure Test

Special Tools Required

- Fuel Pressure Gauge 07406-004000B
- Fuel Pressure Gauge Attachment Set 07AAJ-S6MA150

1. Relieve the fuel pressure See: Fuel Pressure Release > Procedures.

2. Attach the fuel pressure gauge set and the fuel pressure attachment gauge.

pic 1

3. Disconnect the HDS from the DLC (fuel pressure relieving with the HDS) or install PGM-FI main relay 2 (fuel pressure relieving without the HDS).

4. Start the engine, and let it idle.

- If the engine starts, go to step 6.
- If the engine does not start, go to step 5.

5. Check to see if the fuel pump is running: Listen to the fuel filler port with the fuel fill cap removed. The fuel pump should run for 2 seconds when the ignition switch is first turned to ON(II).

- If the pump runs, go to step 6.
- If the pump does not run, check for DTCs, then do the appropriate DTC troubleshooting procedure.

6. Read the fuel pressure gauge. The pressure should be 380-430 kPa (3.9-4.4 kgf/cm2, 55-63 psi).

- If the pressure is OK, the test is complete.
- If the pressure is out of specification, replace the fuel pressure regulator See: Fuel Pressure Regulator > Removal and Replacement and the fuel filter See: Fuel Filter > Removal and Replacement, then recheck the fuel pressure.

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Let us know what you find or if you have other questions.

Take care,
Joe