Misfire - weird symptomps

[mck159]

Hi,

Check engine lightened up on my car (Z4 E89 3.0i) and engine started being shaky in idle -upon reading errors with Bimmerlink, there was single error: misfire on cylinder 5.

I droped it off at local garage straight away (2 miles drive), who promised to fix it - and their computer showed on cylinders 2, 4, 5 and 6, so they decided to change all spark plugs and all ignition coils (without asking me first, but this is another story...)

After doing so, check engine is still on, engine is still shakey and right now it shows only ignition failure on cylinder 5 (code 2E1B) - so different cylinder than initially :|

What is weird about it:
* garage saw errors on 4 cylinders - sounds quite unlikely that spark plug or/and coil on 4 cylinders failed overnight
* now it's showing misfire on different cylinder than initially

Can anyone suggest what could it be and if I can diagnose or attempt fixing it myself? (I have OBD2 reader and most of tools needed - multimeter, socket wrenches, torque wrench)



Btw. garage that I've used left really bad impression - they've charge me £360 for changing spark plugs + coils, without asking me first, and their approach was "lets change parts, and see what happends" (couldn't they just try swapping coils, before deciding to replace them all?) - they also proposed that as next step they gonna change one injector for ~£200, without guaranteeing that it solves the issue - at this point of time I decided to take the car back from them

 

[Mr Tidy]

It sounds like you need to find a better garage!

If you said where you are maybe someone on here would have some recommendations for you.

 

[mck159]

Definitely, really disappointed with this garage - I'd expect them to diagnose the issue, rather than change parts to see if it helps (which i didn't). I don't mind them changing spark plugs, as those would need to be changed in next few years anyway, but instead of installing 6 new coils, they could first swap one coil with another, to see if problem travels to other cylinder... it's literally 2 minutes of work, as they are push/pull

My location is London (E2), UK - I'd really appereciate some good garage recommendations

 

[B21]

I see you’ve posted it on multiple sites..I replied on one of the others..

 

[Busterboo]

B21's comments you've posted this problem on several sites ... I suggest you try several garages, instead, beginning with cheapest - if you're a member - first.

So, call whichever recovery you're with. Might sound silly, but AA, for example, diagnoses very large number of faults every day. I've used them on Jaguar, Porsche, BMW ... they've been really good. On 35iS, the man even did 10-mile round trip to local AD for needed part.

Next, most obvious - indy. Often quite knowledgeable ... more so than 'a' garage.

Finally- shock, horror - AD. Money often solves problems.

 

[raymond.harper]

Check the earth on the coil packs, they tend to share a common one which may explain three cylinders showing fault. Problem could be a faulty injector

 

[Christopher72]

If not already resolved, if you've done the easy and swapped coils with no win, then check the seal on the injector for the misfiring cylinder.

If you can pull out the injector without any effort or testing the injector shows fault -- there's your issue(s). Seals are cheap... injectors not so much, but refurbs aren't horrible.

 

[B21]

Another ‘hopper’…posted the question then ran…not been here since he posted.. :tumbleweed:

 

[BMWZ4MC]

Perhaps all cylinders failed to fire and he’s stranded somewhere in the cold and dark…

 

[B21]

Perhaps all cylinders failed to fire and he’s stranded somewhere in the cold and dark…

:rofl: :rofl: :rofl: