Rough idle when cold, code 10705

Ferruccio · 07-03-2013, 06:16 PM

I get a misfire reading when I start the car after a long time not being driven (about a day when the temperatures are all back to normal). After a few restarts of the engine, everything seems to be fine. What would cause this initial problem which gets better after a few starts? Once the engine is warm, this never happens.

I replaced the plugs and low pressure fuel pump.

Is it the ignition coils or high pressure fuel pump?

Ferruccio · 07-04-2013, 02:09 AM

The answer is either injectors or ignition coils. I am 80% sure. I will migrate some coils to see if the misfire migrates accordingly. I sure hope it does! Injector replacement is a relative PITA and I might just stealership that, given my limited tools.

Ferruccio · 07-05-2013, 01:35 AM

I swapped ignition coils 1 and 2 to see if the misfire would migrate. I did this before starting the engine for the day, so the block was basically room temperature. Upon starting the engine, I got no codes whatsoever and the idle lacked misfires.

Curious about this, I swapped the coils again, back to the position they were at when I got the misfire, and waited a few hours to cool the engine. Upon starting, still no codes. I waited a few more hours for the engine to cool down once more. I tried again, no misfires.

I will be starting the engine again the next day once it is *truly* at room temperature to see if I can get that 10705 code.

I really want to reproduce this problem so I can localize the problem to the ignition coils, but this is an elusive problem.

Anyone have any ideas? Could any of this hard-to-reproduce behavior be attributed to injectors instead of coils, or is the best that can be done at this point the same speculation I am offering in this thread?

Ferruccio · 01-13-2014, 01:48 PM

Turns out the problem is crappy injectors. Injector #6 was completely toast, and was leaking fuel when cold. Eventually, it got to the point that, even warmed up, the engine was misfiring 100% of the time. Injectors #2 and #4 will be the next to go, upon checking for voltages when reprogramming for the replacement #6 injector.

mwahlert · 01-13-2014, 01:53 PM

I am having the same problem - pretty sure it is also an injector issue.

Kish2604 · 01-13-2014, 03:55 PM

Quote:

Originally Posted by Ferruccio

Turns out the problem is crappy injectors. Injector #6 was completely toast, and was leaking fuel when cold. Eventually, it got to the point that, even warmed up, the engine was misfiring 100% of the time. Injectors #2 and #4 will be the next to go, upon checking for voltages when reprogramming for the replacement #6 injector.

Hi, please explain the process of checking voltages... Is it a method of testing the injectors.

I need to change my injectors as well, getting as much information before I change them out.

Thanks...

Ferruccio · 02-25-2014, 11:34 AM

It is something you have to program into the car when you get new injectors. I do not know the details, but I do know that there is some sort of variance in the voltages that each injector has. They are tested, and a voltage (or something) is printed on the side of each part. Those numbers you have to program into the car, so it knows how each injector responds electrically.

924er · 02-27-2014, 01:48 AM

how much was it to replacement

07-03-2013, 06:16 PM	#1
Ferruccio First Lieutenant 40 Rep 373 Posts Drives: 2010 335i Join Date: May 2011 Location: Colorado Springs, CO iTrader: (1)	Rough idle when cold, code 10705 I get a misfire reading when I start the car after a long time not being driven (about a day when the temperatures are all back to normal). After a few restarts of the engine, everything seems to be fine. What would cause this initial problem which gets better after a few starts? Once the engine is warm, this never happens. I replaced the plugs and low pressure fuel pump. Is it the ignition coils or high pressure fuel pump?
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07-05-2013, 01:35 AM	#3
Ferruccio First Lieutenant 40 Rep 373 Posts Drives: 2010 335i Join Date: May 2011 Location: Colorado Springs, CO iTrader: (1)	I swapped ignition coils 1 and 2 to see if the misfire would migrate. I did this before starting the engine for the day, so the block was basically room temperature. Upon starting the engine, I got no codes whatsoever and the idle lacked misfires. Curious about this, I swapped the coils again, back to the position they were at when I got the misfire, and waited a few hours to cool the engine. Upon starting, still no codes. I waited a few more hours for the engine to cool down once more. I tried again, no misfires. I will be starting the engine again the next day once it is truly at room temperature to see if I can get that 10705 code. I really want to reproduce this problem so I can localize the problem to the ignition coils, but this is an elusive problem. Anyone have any ideas? Could any of this hard-to-reproduce behavior be attributed to injectors instead of coils, or is the best that can be done at this point the same speculation I am offering in this thread?
	Appreciate 0 Quote

01-13-2014, 01:53 PM	#5
mwahlert Lieutenant Colonel 95 Rep 1,659 Posts Drives: 2009 335i Join Date: Apr 2008 Location: NC iTrader: (8)	I am having the same problem - pretty sure it is also an injector issue.
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02-25-2014, 11:34 AM	#7
Ferruccio First Lieutenant 40 Rep 373 Posts Drives: 2010 335i Join Date: May 2011 Location: Colorado Springs, CO iTrader: (1)	It is something you have to program into the car when you get new injectors. I do not know the details, but I do know that there is some sort of variance in the voltages that each injector has. They are tested, and a voltage (or something) is printed on the side of each part. Those numbers you have to program into the car, so it knows how each injector responds electrically.
	Appreciate 0 Quote

02-27-2014, 01:48 AM	#8
924er Colonel 352 Rep 2,050 Posts Drives: e92 335i '10 Join Date: Feb 2014 Location: Socal iTrader: (0)	how much was it to replacement
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07-04-2013, 02:09 AM	#2
Ferruccio First Lieutenant 40 Rep 373 Posts Drives: 2010 335i Join Date: May 2011 Location: Colorado Springs, CO iTrader: (1)	The answer is either injectors or ignition coils. I am 80% sure. I will migrate some coils to see if the misfire migrates accordingly. I sure hope it does! Injector replacement is a relative PITA and I might just stealership that, given my limited tools.
	Appreciate 0 Quote

01-13-2014, 01:48 PM	#4
Ferruccio First Lieutenant 40 Rep 373 Posts Drives: 2010 335i Join Date: May 2011 Location: Colorado Springs, CO iTrader: (1)	Turns out the problem is crappy injectors. Injector #6 was completely toast, and was leaking fuel when cold. Eventually, it got to the point that, even warmed up, the engine was misfiring 100% of the time. Injectors #2 and #4 will be the next to go, upon checking for voltages when reprogramming for the replacement #6 injector.
	Appreciate 0 Quote