[Tevurion]

Getting a minor misfire (not enough to fault) whether cold/warm.

Replaced gasket as oil was getting into the wells.

New plugs and coils but still misfiring.

Pulled some plugs and they were wet. smelt of fuel but im not sure if the whole thread is exposed to fuel?

Car also sometimes smells strongly of fuel on startup.


Any help would be appreciated, thanks.

[jwilalex]

Classic symptoms of leaking injector(s).

[david in germany]

What year? My 09 build year n43 E87 had an injector recall. But same engine in the e9x as the e8x. Almost any fuel smell at start up will be a leaky injector.

[Tevurion]

Mine is an 09 too, check with BMW and it has no active recalls.

I've read in a couple of posts that Bosch plugs can cause a few issues so I've got some NGK ones on order.

I'll move onto the injectors after that, thanks guys.

[jwilalex]

Originally Posted by Tevurion

Mine is an 09 too, check with BMW and it has no active recalls.

I've read in a couple of posts that Bosch plugs can cause a few issues so I've got some NGK ones on order.

I'll move onto the injectors after that, thanks guys.

When you compare those Bosch and NGK plugs together you’ll be amazed at the difference in length and understand at that point why the Bosch ones cause problems.

NGK are the proper OEM fit. (ZKBR7A-HTU NGK)

Info here ref N43 engines/spark plugs

[Tevurion]

You're right, difference was way bigger than i thought.

New sparks seemed to have got rid of 90% of the misfire, i'm still fairly certain i can feel it but not sure how much of it is in my head at this point. I'll run it for a week and see how it goes.

Here is a photo out of interest. 1 & 3 had a fair bit of liquid on them and are quite sooty. Only been used for around 1k miles so i'm thinking injectors 1 and 3 depending on how the issue develops.



Edit: Now i think about it, this is sometime after i took them out so surely if it was fuel it would have evaporated by now?

[jwilalex]

Nope still signs of leaking injectors, not forgetting that pic shows the errant Bosch plugs and they’re the wrong length so not been protruding as much. It’s only 4-5mm but that will have had an effect too.

[Tevurion]

Any easy way to tell which ones and which index they are?

Thanks for the help so far.

[jwilalex]

Originally Posted by Tevurion

Any easy way to tell which ones and which index they are?

Thanks for the help so far.

Only way as far as I’m aware is to look at the info printed on it: As shown here.

Also you can’t mix certain index levels. 12 is the latest, if yours are original they’re probably index 9.

BMW TIS - injector replacement

[david in germany]

Originally Posted by jwilalex

Only way as far as I’m aware is to look at the info printed on it: As shown here.

Also you can’t mix certain index levels. 12 is the latest, if yours are original they’re probably index 9.

BMW TIS - injector replacement

09 was around index 5 if they were original.

[Tevurion]

Thanks guys. Got no service history to say they've ever been changed so I'll look at index 5 compatible ones.

Might try swap 1 and 3 so that the suspected leaky ones are on the same bank and replace those first.

[Sayek]

The pain of leaking injectors
Try couple bottles of Liqui Molly injector cleaner. May clean the injectors a little and remove some misfire.

[david in germany]

Originally Posted by Tevurion

Thanks guys. Got no service history to say they've ever been changed so I'll look at index 5 compatible ones.

Might try swap 1 and 3 so that the suspected leaky ones are on the same bank and replace those first.

It is better to just replace them all at once with the newest index 11 or 12 and be done with it.
Part number is 13537589048
Don’t forget your decouplers part number 13537564751

And you will need to code them.