M156 P0300 Misfires when warm
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Joined: Jul 2014
Posts: 3,324
Likes: 585
2005 e55 AMG
Awesome man !!! So glad to hear !!! It really sucks having stuff like this hanging over your head for so long but look how much you/we learned because of it.....unfortunatly !!!!
Last edited by SICAMG; Feb 15, 2026 at 04:05 PM.
Thread Starter
Member
Joined: Nov 2018
Posts: 164
Likes: 54
2006 E55
Hopefully the FINAL Update:
Been waiting to post this for 2 years. Always hate when people open a thread and then don't post a solution, so if you didnt watch the video, it is summarized below:
Root cause: Improper clearance from the front-most cam bridge on bank 1 causes inadequate oil pressure to the cam adjuster, leading to misfires once the ecu tries to control timing.
Not sure why, but after i intially throught the cam bridge that i checked tolerance on and replaced had not fixed the issue, i drove the car hard for 15-20 minutes, reset the ecu, plugged the cam solenoid in, and boom. No more misfires. Car has been driving perfect for 3 weeks and ~500 miles now.
So in the end, this was a self-inflicted issue. The cam bridge that I broke 3 years ago and then replaced with one with unknown tolerance caused all of this. Hindsight being 20/20, i probably should have been suspect of this sooner, but whats weird is it took almost 10k miles for this issue to show up, so i didn't put 2 and 2 together.
Hopefully someone someday learns from this, but unless you break a cam cap, maybe not! Onto the next project....
Been waiting to post this for 2 years. Always hate when people open a thread and then don't post a solution, so if you didnt watch the video, it is summarized below:
Root cause: Improper clearance from the front-most cam bridge on bank 1 causes inadequate oil pressure to the cam adjuster, leading to misfires once the ecu tries to control timing.
Not sure why, but after i intially throught the cam bridge that i checked tolerance on and replaced had not fixed the issue, i drove the car hard for 15-20 minutes, reset the ecu, plugged the cam solenoid in, and boom. No more misfires. Car has been driving perfect for 3 weeks and ~500 miles now.
So in the end, this was a self-inflicted issue. The cam bridge that I broke 3 years ago and then replaced with one with unknown tolerance caused all of this. Hindsight being 20/20, i probably should have been suspect of this sooner, but whats weird is it took almost 10k miles for this issue to show up, so i didn't put 2 and 2 together.
Hopefully someone someday learns from this, but unless you break a cam cap, maybe not! Onto the next project....
