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Discussion Starter #1
So earlier this week I got a code for cylinder 8 misfire changed the plug and the coil problem went away. Car ran good for a day or so and just last night I stared the beast and notices rough idle followed by the "death ding" CEL. plugged in OBD2 and got misfire code on all 10 cylinders. I did noticed really bad smell coming from the tail pipe. To back track a little now. Let my friend use my car and apparently he pumped 87 instead of 93. the next day I did syphon most of the fuel with a hand held pump from home depot cheap solution and pumped with new fresh 93. I was thinking maybe air in my fuel lines that is causing this misfire? Also can it be dirty MAF sensors?
 

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I can say that 87 will not cause any misfire. As for the misfiring... hard to tell. Seem that lately a higher number of injectors stuck open have been seen (due to failing fuel filters), but I wouldn't expect all 10 to fail at the same time.
 

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Octane ratings aren't suggestions. If your car is tuned for 91/93 and you throw in 87 it will cause knock in all cylinders.

Drive it a bit with 93 to make sure all the 87 is out of the system, clear the codes and see if it comes back.
 

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I can say that 87 will not cause any misfire. As for the misfiring... hard to tell. Seem that lately a higher number of injectors stuck open have been seen (due to failing fuel filters), but I wouldn't expect all 10 to fail at the same time.
I was thinking of cleaning my MAF sensor and see if that it the problem.
 

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Octane ratings aren't suggestions. If your car is tuned for 91/93 and you throw in 87 it will cause knock in all cylinders.

Drive it a bit with 93 to make sure all the 87 is out of the system, clear the codes and see if it comes back.
so yeah it could be that 87. I think ill clean my MAFs today and see if that helps any?
 

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Possibly a fuel pressure/supply related issues, or oil pressure related issues.

Maybe injectors are going bad?

As someone stated, when was the fuel filter changed, and how many miles on the car?

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Discussion Starter #7
Possibly a fuel pressure/supply related issues, or oil pressure related issues.

Maybe injectors are going bad?

As someone stated, when was the fuel filter changed, and how many miles on the car?

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can I be that lucky for all 10 to go bad? 118k on the car not sure when was the fuel filter changed I got this car 4 months ago it was built by troy jeup so I know the engine it self is good
 

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Not 100% sure, maybe others can chip in for the likelyhood...but it could be the second thing to look for after doing the MAF clean, which I think is most likely the issue. Here is a link to the DIY E60 M5 Bulletin:


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Not 100% sure, maybe others can chip in for the likelyhood...but it could be the second thing to look for after doing the MAF clean, which I think is most likely the issue. Here is a link to the DIY E60 M5 Bulletin:


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thanks for the link. I'm going to do that today and see. hopefully they just need to be cleaned
 

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Indeed. So don't confuse knocking with misfiring.
Not trying to get snide with you, but knock can cause misfire codes...

All 10 cylinders throwing codes at the same time directly after 87 was thrown in the tank seems pretty cause and effect to me. The chances of all failures of every cylinder at the same time is pretty low, especially if the motor is freshly built recently by the board's "favorite" stroker master engine builder extraordinaire and he just replaced plug and coil on one cylinder and its misfiring with the rest. Also aware that a stock tune shouldn't get as upset with regular in the tank but again if the motor has any kind of tune on it then it will get cranky with lower grade gas. I don't know what troy does regarding tunes for his builds.

My only other thought is that both ionic modules burned out simultaneously for whatever reason.

Great way to be certain if it is or isn't gas quality and a parts failure is to run the 87 out of the system and clear the codes to see if they return.
 

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Discussion Starter #12
Not trying to get snide with you, but knock can cause misfire codes...

All 10 cylinders throwing codes at the same time directly after 87 was thrown in the tank seems pretty cause and effect to me. The chances of all failures of every cylinder at the same time is pretty low, especially if the motor is freshly built recently by the board's "favorite" stroker master engine builder extraordinaire and he just replaced plug and coil on one cylinder and its misfiring with the rest. Also aware that a stock tune shouldn't get as upset with regular in the tank but again if the motor has any kind of tune on it then it will get cranky with lower grade gas. I don't know what troy does regarding tunes for his builds.

My only other thought is that both ionic modules burned out simultaneously for whatever reason.

Great way to be certain if it is or isn't gas quality and a parts failure is to run the 87 out of the system and clear the codes to see if they return.
thank for your input I appreciate it. I had an active code for #10 misfire this Saturday. replaced that coil along with a new plug only on 10. car was good for a day or 2 and now all this mess?
 

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Lol it's the same concept my Snap-On smoker works exactly like that.

Back in the day I used to use cigars.


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Wow it seems like everyone’s s85 decided to start misfiring over the past week, there’s been like 5 threads
 

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Weird. I've been suffering in silence with this issue for months now. I recently started driving exclusively in P500 sport mode and it seems the codes don't come up anymore. I'll continue to drive this way to see if it goes away. Mind you I also have the FAMS tune but I was still getting misfire codes on all cylinders. I'll report my conclusions after a month or so.
 

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I had been experiencing engine misfires this past week and I am thinking crap... start searching sensors, injectors etc. etc. that might need changing. But, at least here in Minnesota under lockdown, no one has been driving, and I always buy the 93 octane gas. So could it be bad gas? throw in a bottle of Seafoam and refill the tank and the issue went away. Maybe that is a big no no for high tech BMW guys, but before there were scary computers to flash every hiccup we just felt that a car wasn't running quite right and sometimes a can of seafoam did wonders :p
 

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Did you by any chance overfill your oil a bit?

Whens the last time you changed your sparkplugs?

i had an issue of misfires on every cylinder from a combination of car sitting around, overfilling the oil and really worn sparkplugs
 

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What I CAN tell you, is that if you have a misfire on 1 cylinder, mainly due to a bad coil, it will report codes on all cylinders. My guess is from the timing getting messed up.
I had a misfire on all 10, and my mechanic tracked it to a bad coil on #6. Replaced only that one, and it's been perfect.
 
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