misfire after changing plugs..

Bts535i · 10-19-2018, 05:14 PM

My car hit 48000 miles so I thought I'd change my plugs seeing I'd get a slight hiccup at idle.

after I changed them I'm now getting a misfire on cyl 4 on med to hard acceleration leading to drivetrain malfunction.
I am no longer getting the hiccup at idle.

I swapped coil 3 and 4 and my misfire remained on cyl 4.

can I get a misfire if I gapped them wrong?

ey2001 · 10-19-2018, 06:12 PM

Quote:

Originally Posted by Bts535i

My car hit 48000 miles so I thought I'd change my plugs seeing I'd get a slight hiccup at idle.

after I changed them I'm now getting a misfire on cyl 4 on med to hard acceleration leading to drivetrain malfunction.
I am no longer getting the hiccup at idle.

I swapped coil 3 and 4 and my misfire remained on cyl 4.

can I get a misfire if I gapped them wrong?

Yes check the plug on 4

ezaircon4jc · 10-19-2018, 06:47 PM

And the connector.

Bts535i · 10-19-2018, 07:16 PM

the connector?

ezaircon4jc · 10-19-2018, 07:38 PM

Quote:

Originally Posted by Bts535i

the connector?

Coil to plug...

Bts535i · 10-20-2018, 10:23 AM

so I haven't had a chance to fixing my car yet but here are some other observations from my car.
I turned my jb4 to map 0 and no misfire at wot.
the plugs I put in were bosch dpl platinum pre gapped at .32 and I bumped down to .28.

should I pull them out and put them back to .32 or dump down to .22 like I see so many talking about.

jonobro · 10-20-2018, 01:26 PM

Quote:

Originally Posted by Bts535i

so I haven't had a chance to fixing my car yet but here are some other observations from my car.
I turned my jb4 to map 0 and no misfire at wot.
the plugs I put in were bosch dpl platinum pre gapped at .32 and I bumped down to .28.

should I pull them out and put them back to .32 or dump down to .22 like I see so many talking about.

Where'd you get this picture from

Bts535i · 10-20-2018, 01:37 PM

my phone off of my jb4 app that's hooked up to my misfiring car.
why what's up

Bts535i · 10-21-2018, 12:36 PM

so after chasing the misfire for the past 3 hours it came down to 2 out of the 6 new bocsh plugs I was sold were bad..

NinetyEight740 · 10-22-2018, 07:27 AM

Quote:

Originally Posted by Bts535i

so after chasing the misfire for the past 3 hours it came down to 2 out of the 6 new bocsh plugs I was sold were bad..

Did you torque them properly? The plugs are very temperamental, if over torqued they break internally...

Bts535i · 10-22-2018, 07:37 AM

I believe so.. 17lbs I believe

NinetyEight740 · 10-24-2018, 01:24 AM

Quote:

Originally Posted by Bts535i

I believe so.. 17lbs I believe

Spec is 23nm plus or minus 3, so yea 17 ft lb is about right. I’ve had bad plugs which we can only guess were damaged in shipping. 🤷🏻*♂️

Bts535i · 10-24-2018, 05:07 AM

got 2 new ones and all is good..

matroxstock · 10-25-2018, 01:07 PM

Check the plug gap, either that is bad or the plug is bad. To find out if it is a bad plug, switch it with another cylinder.

10-19-2018, 05:14 PM	#1
Bts535i Private 7 Rep 58 Posts Drives: 2012 535i xdrive Join Date: Sep 2018 Location: New York iTrader: (0)	misfire after changing plugs.. My car hit 48000 miles so I thought I'd change my plugs seeing I'd get a slight hiccup at idle. after I changed them I'm now getting a misfire on cyl 4 on med to hard acceleration leading to drivetrain malfunction. I am no longer getting the hiccup at idle. I swapped coil 3 and 4 and my misfire remained on cyl 4. can I get a misfire if I gapped them wrong?
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10-19-2018, 06:47 PM	#3
ezaircon4jc Major General 4451 Rep 5,337 Posts Drives: 2019 540i M Sport Join Date: Jan 2015 Location: San Diego iTrader: (0)	And the connector.
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10-19-2018, 07:16 PM	#4
Bts535i Private 7 Rep 58 Posts Drives: 2012 535i xdrive Join Date: Sep 2018 Location: New York iTrader: (0)	the connector?
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10-20-2018, 10:23 AM	#6
Bts535i Private 7 Rep 58 Posts Drives: 2012 535i xdrive Join Date: Sep 2018 Location: New York iTrader: (0)	so I haven't had a chance to fixing my car yet but here are some other observations from my car. I turned my jb4 to map 0 and no misfire at wot. the plugs I put in were bosch dpl platinum pre gapped at .32 and I bumped down to .28. should I pull them out and put them back to .32 or dump down to .22 like I see so many talking about. Attached Images
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10-20-2018, 01:37 PM	#8
Bts535i Private 7 Rep 58 Posts Drives: 2012 535i xdrive Join Date: Sep 2018 Location: New York iTrader: (0)	my phone off of my jb4 app that's hooked up to my misfiring car. why what's up
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10-21-2018, 12:36 PM	#9
Bts535i Private 7 Rep 58 Posts Drives: 2012 535i xdrive Join Date: Sep 2018 Location: New York iTrader: (0)	so after chasing the misfire for the past 3 hours it came down to 2 out of the 6 new bocsh plugs I was sold were bad..
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10-22-2018, 07:37 AM	#11
Bts535i Private 7 Rep 58 Posts Drives: 2012 535i xdrive Join Date: Sep 2018 Location: New York iTrader: (0)	I believe so.. 17lbs I believe
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10-24-2018, 05:07 AM	#13
Bts535i Private 7 Rep 58 Posts Drives: 2012 535i xdrive Join Date: Sep 2018 Location: New York iTrader: (0)	got 2 new ones and all is good..
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10-25-2018, 01:07 PM	#14
matroxstock New Member 7 Rep 13 Posts Drives: 2011 BMW 535i Join Date: Jul 2018 Location: CA iTrader: (0)	Either plug gap or bad plug Check the plug gap, either that is bad or the plug is bad. To find out if it is a bad plug, switch it with another cylinder.
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