Disasterh as befallen the ballistic missile (P0300)
01-27-2020, 01:18 AM
#1
Super Member
Thread Starter
Disaster hath befallen the ballistic missile (P0300)
Now I am scared.
I wasn't scared before, but now I am scared. That which I feared has happened.
Drive fine; no problem.... accelerate hard and BAM CEL (initially flashing), followed by intense vibration.
Clues point to coil packs, but I still want to do a proper diagnostics on it before crying and parting with my precious money.
Finally got my generic OBD2 scanner, and initially I got P0311 (cylinder 11 misfire), then P0312 (cylinder 12 misfire), then finally P0300... multiple random misfires. Driver's side cylinders.
Coil packs and spark plugs are allegedly new. I say allegedly, b/c this is on a verbal promise and a handshake.
The fuel filter was last replaced in 2011, 60k miles ago. I've gone ahead and bought a new MANN W 720 fuel filter, as this is a relatively simple repair that needs to be done regardless, and may resolve the issue. Beyond that, what other potential issues can cause this problem?
This sucks especially because the car cannot be run while in this condition.
I wasn't scared before, but now I am scared. That which I feared has happened.
Drive fine; no problem.... accelerate hard and BAM CEL (initially flashing), followed by intense vibration.
Clues point to coil packs, but I still want to do a proper diagnostics on it before crying and parting with my precious money.
Finally got my generic OBD2 scanner, and initially I got P0311 (cylinder 11 misfire), then P0312 (cylinder 12 misfire), then finally P0300... multiple random misfires. Driver's side cylinders.
Coil packs and spark plugs are allegedly new. I say allegedly, b/c this is on a verbal promise and a handshake.
The fuel filter was last replaced in 2011, 60k miles ago. I've gone ahead and bought a new MANN W 720 fuel filter, as this is a relatively simple repair that needs to be done regardless, and may resolve the issue. Beyond that, what other potential issues can cause this problem?
This sucks especially because the car cannot be run while in this condition.
Last edited by Fried Chicken; 01-27-2020 at 07:21 PM.
01-27-2020, 05:25 AM
#2
Now I am scared.
I wasn't scared before, but now I am scared. That which I feared has happened.
Drive fine; no problem.... accelerate hard and BAM CEL (initially flashing), followed by intense vibration.
Clues point to coil packs, but I still want to do a proper diagnostics on it before crying and parting with my precious money.
Finally got my generic OBD2 scanner, and initially I got P0311 (cylinder 11 misfire), then P0312 (cylinder 12 misfire), then finally P0300... multiple random misfires. Driver's side cylinders.
Coil packs and spark plugs are allegedly new. I say allegedly, b/c this is on a verbal promise and a handshake.
The fuel filter was last replaced in 2011, 60k miles ago. I've gone ahead and bought a new MANN W 720 fuel filter, as this is a relatively simple repair that needs to be done regardless, and may resolve the issue. Beyond that, what other potential issues can cause this problem?
This sucks especially because the car cannot be run while in this condition.
I wasn't scared before, but now I am scared. That which I feared has happened.
Drive fine; no problem.... accelerate hard and BAM CEL (initially flashing), followed by intense vibration.
Clues point to coil packs, but I still want to do a proper diagnostics on it before crying and parting with my precious money.
Finally got my generic OBD2 scanner, and initially I got P0311 (cylinder 11 misfire), then P0312 (cylinder 12 misfire), then finally P0300... multiple random misfires. Driver's side cylinders.
Coil packs and spark plugs are allegedly new. I say allegedly, b/c this is on a verbal promise and a handshake.
The fuel filter was last replaced in 2011, 60k miles ago. I've gone ahead and bought a new MANN W 720 fuel filter, as this is a relatively simple repair that needs to be done regardless, and may resolve the issue. Beyond that, what other potential issues can cause this problem?
This sucks especially because the car cannot be run while in this condition.
yes probably is coil pack fail
if the whole side goes wrong then it can also be your voltage transformer
Maybe now you need real Xentry where you can see fault counter and 500x more info
The following 2 users liked this post by pmercury:
biker349 (01-27-2020),
Fried Chicken (02-02-2020)
01-27-2020, 07:44 PM
#3
Super Member
Thread Starter
I hooked it up to a real MB computer with DAS (does Xentry give more than DAS?).
I did a fuel injector test and I got a few wonky issues on the suspect cylinder (11). The difficulty of the diagnosis is the issue seems to present only under strong load.
I didn’t hook up the fuel rail for pressure testing. Again, only under WOT does the issue present (independent of RPMs). I will be replacing the fuel filter and running some liqui moly fuel-**** cleaner
into the system.
If that doesn’t solve the issue, I’ll double check everything, and gap the spark plugs to a recommended 26/1000’s of an inch, as well as visually inspect the coils.
Should the car still present with issues, I’ll be replacing the coil pack with one from http://www.v12icpack.com (Clark is pretty damn impressive).
I did a fuel injector test and I got a few wonky issues on the suspect cylinder (11). The difficulty of the diagnosis is the issue seems to present only under strong load.
I didn’t hook up the fuel rail for pressure testing. Again, only under WOT does the issue present (independent of RPMs). I will be replacing the fuel filter and running some liqui moly fuel-**** cleaner
into the system.
If that doesn’t solve the issue, I’ll double check everything, and gap the spark plugs to a recommended 26/1000’s of an inch, as well as visually inspect the coils.
Should the car still present with issues, I’ll be replacing the coil pack with one from http://www.v12icpack.com (Clark is pretty damn impressive).
01-28-2020, 06:50 AM
#4
I hooked it up to a real MB computer with DAS (does Xentry give more than DAS?).
I did a fuel injector test and I got a few wonky issues on the suspect cylinder (11). The difficulty of the diagnosis is the issue seems to present only under strong load.
I didn’t hook up the fuel rail for pressure testing. Again, only under WOT does the issue present (independent of RPMs). I will be replacing the fuel filter and running some liqui moly fuel-**** cleaner
into the system.
If that doesn’t solve the issue, I’ll double check everything, and gap the spark plugs to a recommended 26/1000’s of an inch, as well as visually inspect the coils.
Should the car still present with issues, I’ll be replacing the coil pack with one from http://www.v12icpack.com (Clark is pretty damn impressive).
I did a fuel injector test and I got a few wonky issues on the suspect cylinder (11). The difficulty of the diagnosis is the issue seems to present only under strong load.
I didn’t hook up the fuel rail for pressure testing. Again, only under WOT does the issue present (independent of RPMs). I will be replacing the fuel filter and running some liqui moly fuel-**** cleaner
into the system.
If that doesn’t solve the issue, I’ll double check everything, and gap the spark plugs to a recommended 26/1000’s of an inch, as well as visually inspect the coils.
Should the car still present with issues, I’ll be replacing the coil pack with one from http://www.v12icpack.com (Clark is pretty damn impressive).
Das is part of Xentry
depending on what year the car is it switches to DAS or remains in Xentry new interface
most important is the features, and that really depend on where you got the installation from
01-28-2020, 01:36 PM
#5
Super Member
Thread Starter
Yeah he was very understanding when I told him I will do everything in my power to not give him my business
I think the version I used is straight from Mercedes. O2 sensors checked out. Fuel Injectors seemed wonky but not totally unreliable... would that cause a misfire on cylinders 11 and 12 under acceleration?
I was obsessing over the issue last night and someone else had the exact same issue (CEL under acceleration) and it seems spark plugs were the culprit.. the coil packs could be saved if the car isn’t driven. Car is going to stay warm and toasty in the garage until I find and clean out my spark plugs.
Das is part of Xentry
depending on what year the car is it switches to DAS or remains in Xentry new interface
most important is the features, and that really depend on where you got the installation from
depending on what year the car is it switches to DAS or remains in Xentry new interface
most important is the features, and that really depend on where you got the installation from
I was obsessing over the issue last night and someone else had the exact same issue (CEL under acceleration) and it seems spark plugs were the culprit.. the coil packs could be saved if the car isn’t driven. Car is going to stay warm and toasty in the garage until I find and clean out my spark plugs.
The following users liked this post:
biker349 (01-28-2020)
02-02-2020, 04:58 PM
#6
Super Member
Thread Starter
I just pulled the spark plugs. They were *drenched* in oil. I have never seen anything like that before. Will report as I work on this.
02-02-2020, 07:48 PM
#7
The following users liked this post:
Fried Chicken (02-02-2020)
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02-02-2020, 07:50 PM
#8
Super Member
Thread Starter
I also noticed a bunch of sooty-**** on the pistons.
I’ve posted a continuation to this thread here:
https://mbworld.org/forums/m275-v12-...ml#post7970423
02-16-2020, 03:43 AM
#9
My two cents:
While reading through the forums the other day, I came across a similar case. The culprit happened to be a clogged catalytic converter. It could swallow enough exhaust gas under light driving, but on heavy loads it couldn't, generated back pressure, and ECU intervened to protect engine (or O2 sensors, I don't remeber well). If it is only one of the catalytic converters it will only affect one cylinder bank (rings a bell, eh?)
Te best thing is that it is easy to check by physically removing the affected side O2 sensor. Exhaust gas will "escape" through the hole, there will be no pressure buildup and the misfiring episode will not show up. Solution if that is the case: empty the catalytic converter ("gut" it, they said).
While reading through the forums the other day, I came across a similar case. The culprit happened to be a clogged catalytic converter. It could swallow enough exhaust gas under light driving, but on heavy loads it couldn't, generated back pressure, and ECU intervened to protect engine (or O2 sensors, I don't remeber well). If it is only one of the catalytic converters it will only affect one cylinder bank (rings a bell, eh?)
Te best thing is that it is easy to check by physically removing the affected side O2 sensor. Exhaust gas will "escape" through the hole, there will be no pressure buildup and the misfiring episode will not show up. Solution if that is the case: empty the catalytic converter ("gut" it, they said).
The following users liked this post:
biker349 (02-16-2020)
02-16-2020, 08:21 PM
#10
Super Member
Thread Starter
My two cents:
While reading through the forums the other day, I came across a similar case. The culprit happened to be a clogged catalytic converter. It could swallow enough exhaust gas under light driving, but on heavy loads it couldn't, generated back pressure, and ECU intervened to protect engine (or O2 sensors, I don't remeber well). If it is only one of the catalytic converters it will only affect one cylinder bank (rings a bell, eh?)
Te best thing is that it is easy to check by physically removing the affected side O2 sensor. Exhaust gas will "escape" through the hole, there will be no pressure buildup and the misfiring episode will not show up. Solution if that is the case: empty the catalytic converter ("gut" it, they said).
While reading through the forums the other day, I came across a similar case. The culprit happened to be a clogged catalytic converter. It could swallow enough exhaust gas under light driving, but on heavy loads it couldn't, generated back pressure, and ECU intervened to protect engine (or O2 sensors, I don't remeber well). If it is only one of the catalytic converters it will only affect one cylinder bank (rings a bell, eh?)
Te best thing is that it is easy to check by physically removing the affected side O2 sensor. Exhaust gas will "escape" through the hole, there will be no pressure buildup and the misfiring episode will not show up. Solution if that is the case: empty the catalytic converter ("gut" it, they said).
The following users liked this post:
BoxxMann (02-18-2020)
02-18-2020, 02:53 PM
#11
Junior Member
I have a P308/305/300 on my CL500 - can someone give me the cylinder numbering and firing order for the M113 engine...loads of conflicting information out there. @Fried Chicken I'm suspicious that those coil packs are new...and the 600's like to have them replaced 
02-18-2020, 03:03 PM
#12
Super Member
Thread Starter
I’ve posted a continuation to this thread here:
https://mbworld.org/forums/m275-v12-...ml#post7970423
https://mbworld.org/forums/m275-v12-...ml#post7970423
