[CarAbuser]

Looking for the opinions of people more mechanically seasoned than myself.

Decided to pull my spark plugs today hoping to diagnose my rough idle. Was expecting to see wet plugs pointing to bad injectors as the car emits a strong fuel smell on cold starts.

The plugs were all fairly dry, plug5 had some damp patches but not soaking wet.
They have been in the car for 15k miles, 10k of those tuned.

I'm a bit worried about the blackening on the thread, is that standard or something more sinister?

Plug 5 was really black on 1 side so I'm thinking the spray pattern on that one is off. I have swapped all the plugs and coils and been for a long drive, so I'll re-inspect in the morning.

[Underground6t9]

They look good, looks like you're running a little rich, but that's okay.

[jlcf22]

plug 3 doesn't look good you might have a leaky injector did it smell like fuel?

[CarAbuser]

Originally Posted by jlcf22

plug 3 doesn't look good you might have a leaky injector did it smell like fuel?

I thought I got a smell of fuel when I pulled them but I did the same again this morning after switching plugs and coils around then resetting all adaptions and they all seemed fine.

I moved the plugs from cyl3 and cyl5 into cyl4 and cyl6 and all plugs seemed pretty clean this morning. I went for a good drive last night after swapping them around and it seems to have cleaned the dirty plugs in 4 and 6 without gunking up the plugs in 3 and 5.

I do think the injectors in those cylinders may be slightly off but not bad enough to give the dealer reason to replace them. My injectors have part number "1353 7585261-05" which means they are the originals from when the car was built.

[kaigoss69]

Injectors 3 and 5 look to be bad. Anyway, dealer has to replace them due to the recall unless you're out of warranty.

[CarAbuser]

Originally Posted by kaigoss69

Injectors 3 and 5 look to be bad. Anyway, dealer has to replace them due to the recall unless you're out of warranty.

I'm in the UK so no recall. We don't get much in the way of recalls here, even if there is a serious fault you have to ask them to do the work rather than them contact you.

I took a lot at a few US injector recall threads and they all specify 2007-2008 build dates, I'm 2009 and my part numbers don't match the PUMA article I found. If however there is one that covers my injectors then I could use it as leverage for them to investigate further as I have a good relationship with my dealership.

If the car throws a code I will get them replaced as part of the BMW extended warranty the car has.

[Ilma]

I think that injectors can initially start to leak during cold starts.....which is why you would pull the plugs right after startup.

Once they warmup borderline injectors seem to run fine during normal driving and your plugs would get burned clean by normal combustion.

Just saying that poor idle and wet/fouled plugs are probably an indicator but the injector might run fine during normal engine operation.

Still though....it could be an early warning sign that the injector may progressively get worse.

I guess that if you start to get high rpm misfires then that could be a sign that the injector is getting worse.

[CarAbuser]

Originally Posted by Ilma

I think that injectors can initially start to leak during cold starts.....which is why you would pull the plugs right after startup.

Once they warmup borderline injectors seem to run fine during normal driving and your plugs would get burned clean by normal combustion.

Just saying that poor idle and wet/fouled plugs are probably an indicator but the injector might run fine during normal engine operation.

Still though....it could be an early warning sign that the injector may progressively get worse.

I guess that if you start to get high rpm misfires then that could be a sign that the injector is getting worse.

I pulled them twice after cold starts. Followed guidance I read from another member on here about letting the car idle for 20seconds after a cold start then pulling the plugs and checking for moisture.

It does take a while to get to each plug and I'm not sure how long they stay wet for after a cold start. I only noticed a small amount of moisture on plug 5 on my first try.

The car runs fine (touch wood) at higher RPM even with the tune. Not had any misfires and timing looks strong on all cylinders once the revs climb.

As soon as I get a code logged in relation to the injectors I'll take it straight to the dealership.

[CarAbuser]

Quick update on the situation;

Started my car up and noticed it running really rough, expected it to clear itself but it just got worse, then got a flashing yellow engine symbol on the dash and limp mode. Running like shit on 3cylinders and stinking of fuel.
Was in really busy traffic so kept going until I could find somewhere to stop (drove for about half a mile). I stopped the engine and tried to restart but the car just stalled.

Called BMW assist and arranged a pickup and noticed a really strong fuel smell and a low fuel warning on the dash. Checked around the car and there was fuel pouring from both exhausts.

The car was towed to the nearest dealership for repair and I left it with them. They have just called saying that they are replacing all 6 injectors and that the plugs need changing too.

Things went from a slightly black plug to full injector failure very fast!

I'm a bit worried that in the process of the injectors failing that the engine has been damaged. Especially since it seems that fuel was just freely pouring out of the exhausts.
Maybe even damaged exhaust system?

[3.1L Z]

You're fine. Just an injector that was stuck open

[CarAbuser]

Originally Posted by 3.1L Z

You're fine. Just an injector that was stuck open

I'm actually glad the injectors failed, they just chose the worst place to let go.

Does fuel on the cats not cause issues?

[ThatRWD]

Weird how so many injectors are failing now all of a sudden, bad injectors can cause a rod bearing to go, killing your engine. Be careful guys.

[Jeff@TopGearSolutions]

Anyone with the old injectors is just playing with the devil. In the states most of those originals were replaced under recall, however, even those revisions were failing eventually I think -11 or -10 (cant recall the exact number that was used).

There was also some shoddy installation done by the dealers too, like broken tabs and missing decouplers, ETC.

3 and 5 looked fouled in some fashion. It makes sense too that it's possibly a leaky injector an injector stuck open at one point.

I'd check them after a 1000 miles and see if you notice that 3 and 5 become fouled in comparison to the rest. You may want to purchase a few injectors now for that rainy day or just replace all of them now so you don't need to worry, depending on your budget of course.

It's typical when these things go wrong it happens at the worst time.

[CarAbuser]

Originally Posted by Jeff@TopGearSolutions

Anyone with the old injectors is just playing with the devil. In the states most of those originals were replaced under recall, however, even those revisions were failing eventually I think -11 or -10 (cant recall the exact number that was used).

There was also some shoddy installation done by the dealers too, like broken tabs and missing decouplers, ETC.

3 and 5 looked fouled in some fashion. It makes sense too that it's possibly a leaky injector an injector stuck open at one point.

I'd check them after a 1000 miles and see if you notice that 3 and 5 become fouled in comparison to the rest. You may want to purchase a few injectors now for that rainy day or just replace all of them now so you don't need to worry, depending on your budget of course.

It's typical when these things go wrong it happens at the worst time.

Thankfully they have replaced all 6 injectors along with the plugs. In the last year that's a new HPFP, LPFP and all new plugs and injectors. So my fuel system should all be modernised!

I'll check the part numbers of the injectors when I get the car back but from reading REALOEM it looks like they discontinued my original injectors so I'm hoping I will get nice new revised ones.

[Jeff@TopGearSolutions]

Originally Posted by CarAbuser

Thankfully they have replaced all 6 injectors along with the plugs. In the last year that's a new HPFP, LPFP and all new plugs and injectors. So my fuel system should all be modernised!

I'll check the part numbers of the injectors when I get the car back but from reading REALOEM it looks like they discontinued my original injectors so I'm hoping I will get nice new revised ones.

Woops, I just read that as you replied. Good news!

[Rickygst]

I would also change the oil

[CarAbuser]

Originally Posted by Rickygst

I would also change the oil

The oil was changed at the same dealership less than 1k miles ago.

Is there anything to suggest that injector failure would contaminate the oil?

[ThatRWD]

Why is filthy bitches one of the tags

[E90_831]

My car also had this rough idle at cold start situation. Dealer had my car for about 2 weeks when then finally decided to replace all 6 injectors, LPFP and "goodwill" 6 spark plugs under CPO.