[Sparky68]

Suggestions on a postcard please

Pulled the plugs after the misfires coming back up from the Med last month and the back 3 are noticeably blacker than the front 3.

Oxygen sensor maybe? Going to order some iridium plugs and see if that helps. Anything else to look at?

[AlanYoro35i]

Hey sparky ,

I had 2 that was black and others have told me its leaky injectors?? You should look into that area too, i still not have confirmed yet as i'm waiting for parts for service then i will get them to check it.

[Sparky68]

Found out what it is i think mate, leaky valve gasket cover is leaking oil into the plugs, easy enough fix i hope.

[AlanYoro35i]

Originally Posted by Sparky68

Found out what it is i think mate, leaky valve gasket cover is leaking oil into the plugs, easy enough fix i hope.

I think i have that too,

http://www.e90post.com/forums/showthread.php?t=862172

If you look at the photo you can see some oil residue on the top of the thread which probably mean i have leaky gasket cover. parts are inexpensive but alot of labour unless you are planning to do it yourself?

By the way if you do get parts for it, please forward me the part no =]

[Sparky68]

I have a mate that will do it for me, I'd end up with lots of leftover bits and a puzzled look on my face if i did it lol.

[nicktyler]

I had this and also rough idle on cold start. Plugs and coils were changed, no joy. I then thought it was injectors but turned out to be the O2 sensor.

[Sparky68]

Will check the o2 sensor Nick. Got the gasket but, trying to figure out if the bolts need to be replaced. Spoke to 2 BMW techs, 1 at a Indy and 1 at BMW MK. Guess which one said replace them

[idnan]

Originally Posted by Sparky68

Will check the o2 sensor Nick. Got the gasket but, trying to figure out if the bolts need to be replaced. Spoke to 2 BMW techs, 1 at a Indy and 1 at BMW MK. Guess which one said replace them

You only really need to replace aluminium bolts on our cars and they're all steel on the valve cover.

If anyone needs rear o2 sensors, then I have two of the splice in genuine Bosch ones which I don't need.

[Sparky68]

Hey mate, cheers for the info. Hows the car? Got the new kit fitted yet?

[idnan]

Car is ok thanks. I made myself an OEM harness for the meth kit so I don't need to splice into the original loom much. Unfortunately though I haven't got around to fitting it all together yet. If weather is good on Sunday I'll make a start.

I've decided to get my car tuned by Pro Tuning Freaks on and off methanol so I'm driving on the first non-meth map and it is quicker than it's ever been before And that's the base map!

Can't wait till I get it tuned for meth, I'm actually scared! Switching to the Cobb AP was one of the best moves I've made, just a bit gutted that if I decide to upgrade to the V3 unit I'll be without a tune for 3 weeks. Maybe I'll flash with the BT cable if I can find a suitable map.

PS you can have the rear O2s for free if you want Mark.

[Sparky68]

That sounds promising. Prefer the cobb to the JB4? Been talking to Devilsown about mine and they reckon I wont need catless downpipes for their kit.

[idnan]

I prefer the Cobb AP only for the improvement in consistency as the G5 ISO just didn't agree with my car. As soon I cut the transistor things I lost 2-3psi in boost and the car felt like shit. The logs looked fine but it just didn't perform how it should've given the mods/fuel.

You can run meth without the DPs but you'll improve spool and have lower EGTs going catless. Buy the JB4 FSB from BMS and you'll have a better failsafe with the JB4 controlling the meth system.

[Sparky68]

Update, gasket replaced, still mis firing like a mofo!!!! Which O2 sensor do i need?

Anyone have a part number, its the back 3 cylinders if that makes a difference.

Cheers

[MERLIN335i]

Originally Posted by Sparky68

Update, gasket replaced, still mis firing like a mofo!!!! Which O2 sensor do i need?

Anyone have a part number, its the back 3 cylinders if that makes a difference.

Cheers

Pre-cat O2 sensors.

ETK does not give bank ID, just cable length, also colour coded cables Black & Grey. You can see them clearly from above so you can ID which colour is for 4,5,6.

11-78-7-558-055 (1400mm cable)

11-78-7-558-087 (1200mm cable)

HTH

Michael.

[Sparky68]

Thanks Michael

[Sparky68]

Well this has been a interesting day, car went in for the sensor today, luckily for me my indy is a quality guy and found the cause.

The issue that has been dogging me from day 1 on this car [ not making boost targets etc] have all been cured.

[nicktyler]

So changing the O2 sensor cured all the problems? Great news!

It did the same for me too. I'm sure the car has never run as smooth as it does now, I just diddn't know that it wasn't normal before.

[Sparky68]

Should of explained it better Nick, didn't need the sensor, all my issues were from a lower boost pipe not quite sealing properly!

Money I have spent replacing bit's on this car that i never needed too!

Oh well at least all the bits that can fail have been replaced

[AlanYoro35i]

Originally Posted by Sparky68

Should of explained it better Nick, didn't need the sensor, all my issues were from a lower boost pipe not quite sealing properly!

Money I have spent replacing bit's on this car that i never needed too!

Oh well at least all the bits that can fail have been replaced

I had the opposite of you, i had my chargepipe replaced since there was a hole in the rubber haha..i'm finally meet boost target too!

[Sparky68]

Will have to get it out for a blast tomorrow and log what boost its hitting.

[MERLIN335i]

Originally Posted by Sparky68

Should of explained it better Nick, didn't need the sensor, all my issues were from a lower boost pipe not quite sealing properly!

Are you going to check bank 2 plugs, to see if they are the correct colour now you have found the leak ??? Just because it goes better, doen't mean to say it doesn't still have an O2 sensor problem, and could go even better

[1275rob]

Originally Posted by nicktyler

I had this and also rough idle on cold start. Plugs and coils were changed, no joy. I then thought it was injectors but turned out to be the O2 sensor.

Hi Nick, have exactly the same symptoms on my 320i. Had a diagnostic check which is bringing up fault for the N/ox sensor and also carbon in the cats. My indy said I need to either change the cats / sensors ( 3k cost ) or burn premium rate fuel through engine on long journeys for a couple of months to get rid of carbon.
I changed Coils and plugs and the car runs great except for those first couple of minutes in the morning.Do you think that by changing just the o2 sensor will cure this ?