Cylinder six misfire?

2008 HONDA ODYSSEY
155,000 MILES • V6 • AUTOMATIC
Avatar
KAD
  • MEMBER
  • 3 POSTS
I did engine maintenance at a local mechanic in my area. The problem started when I scanned the car and read live data, the misfire rate was increasing rapidly at cylinder 6! However, this misfire occurs only at Idle (both cold and warm). In addition, when I remove the map sensor in which the baro sensor is included in, the misfire disappears. What could be the problem? And how can I fix this problem! Thanks in advance for your help guys!!
Jul 25, 2023 at 3:05 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.
Advertisement
Avatar
JACOBANDNICKOLAS
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 110,190 POSTS
Hi,

It sounds like a faulty sensor. When you disconnect it, it forces the PCM to run the engine on a factory preset. If the misfire goes away, that is my first suspect.

Is the P0306 the only code you are getting? Also, it is odd that it would only affect cylinder 6. If I understand, there wasn't an issue until you scanned live data, correct?

Let me know.

Joe
Jul 26, 2023 at 8:40 PM
Advertisement
Avatar
KAD
  • MEMBER
  • 3 POSTS
Hi,

Thank you for your reply!
Yeah, when I disconnect the sensor, the misfire goes away.

The code P0306 is the only code showing up.

The problem started since I first turned the engine on, then I went to read the live data using my scanner and saw a huge misfire rate at cylinder 6, like more than 2,000, then at cylinder one about 12, and at cylinder 3 the misfire rate is like 8 or 9.
Jul 26, 2023 at 8:48 PM
Avatar
JACOBANDNICKOLAS
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 110,190 POSTS
Hi,

If it started when you connected the scan tool, it may have been happening prior. If it runs properly with the sensor disconnected, that is my first suspect. Have you tried replacing it?

Let me know.

Joe
Jul 27, 2023 at 8:01 PM
Avatar
KAD
  • MEMBER
  • 3 POSTS
Hi Joe,

I tried to replace the sensor, but I couldn't buy a new one which costs around 350$ before I make sure that the problem is the sensor and not something else.

Khaled
Jul 28, 2023 at 12:25 AM
Avatar
JACOBANDNICKOLAS
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 110,190 POSTS
Hi,

I totally understand. Wow, I wouldn't have expected it to be that much.

Here is the thing. I have diagnostics related to the MAP sensor, but they are different based on codes. I could be sending you on a wild goose chase. I don't want to do that.

Take a look at the pic below. That is what I'm seeing. Is there one in specific that you feel would be relevant? I could send all of them to you, but that will certainly be extensive and likely make you want to throw the computer at me. LOL

Take a look and let me know. If I can help, I will.

Take care,

Joe

See pic below.
Image (Click to enlarge)
Attached Media
Jul 28, 2023 at 6:58 PM