2008 630i Intermittent misfire

[Glutton]

Ok, so I’m currently running a 2008 630i on 57k miles. It’s recently developed a slight misfire at low revs, usually between 1.5k and 2.5k revs on part throttle. Higher up the rev range there is no issue and equally on heavy throttle it’s fine. It’s usually just a slight cough then no issue and it can drive for thirty minutes and have no issues. Has anyone encountered similar issues?

[bmwmike]

N53? If so see similar recent thread for a 530i e60. Turned out to be injectors iirc.

[Bowlers]

I had a very similar issue to what you are describing (M54 engine). Ignition coil was failing, replaced and cured it.

[axel1990chp]

Glutton said:

Ok, so I’m currently running a 2008 630i on 57k miles. It’s recently developed a slight misfire at low revs, usually between 1.5k and 2.5k revs on part throttle. Higher up the rev range there is no issue and equally on heavy throttle it’s fine. It’s usually just a slight cough then no issue and it can drive for thirty minutes and have no issues. Has anyone encountered similar issues?

Is it only from cold Glutton?

As mike stated above, my thread a few posts back on this forum has a similar issue. Unfortunately it turned out to be pretty expensive, 65k miles on an N53 which I'm assuming yours is?

Went through plenty and it ended up being the Injectors. Highlighted as 1 during misfire when reading errors but when they took the injectors out on the ITSA thingy ma bobby 2 were in need of replacement. They aren't cheap. Managed to get them at £440 a piece direct from BMW for all 6 and walking away with a 3 year warranty on unlimited mileage. £3150 my bill.

Heres the post!

https://www.pistonheads.com/gassing/topic.asp?h=0&...

[Glutton]

Yep it’s an N53, so injectors is the worry. That said the previous owner had replaced one coil pack and you’d assume they’d all have a similar life span so that may also be worth investigating. I’ve done 340 miles in it this week and it’s been fine. Im not sure how clever the ECU’s are on these would it store a fault that doesn’t trigger an EML?

[bmwmike]

Glutton said:

Yep it’s an N53, so injectors is the worry. That said the previous owner had replaced one coil pack and you’d assume they’d all have a similar life span so that may also be worth investigating. I’ve done 340 miles in it this week and it’s been fine. Im not sure how clever the ECU’s are on these would it store a fault that doesn’t trigger an EML?

Yes there will likely be codes

[axel1990chp]

Glutton said:

Yep it’s an N53, so injectors is the worry. That said the previous owner had replaced one coil pack and you’d assume they’d all have a similar life span so that may also be worth investigating. I’ve done 340 miles in it this week and it’s been fine. Im not sure how clever the ECU’s are on these would it store a fault that doesn’t trigger an EML?

There was definitely fault codes without the EML for me.
Some slightly positive news for you though, I’ve just had all 6 injectors done, ECU software update too, all injectors coded… still having the same problem.
So it might not be injectors