[Russbmw]

I've seen the painfully long thread on the 2 ltr petrol engine. However, I'm confused - let me elaborate.

About a year ago, the EML came on one morning, and the car wouldn't idle. The revs would drop, car stalled, then would automatically restart itself immediately (no starting issues), revs drop, stall, restart.....repeat.

However, the car drove fine despite this - provided you didn't need to stop!. No discernable loss of power.

I checked the car with GT1/EasyDIS, nothing seemed amiss - no more than the usual codes that the car has had since we got it which are that the thermostat has got stuck and the cat has "high sulpuhurisation". Neither of which are showing as something that would flag the EML.

Anyway, knowing about the coil pack issue, i called BMW and discovered our car hadn't had them changed.

Got that done and no issues since........until just before Christmas, when the car did the same thing again. Didn't stall or anything - in fact, ran no different at all, just got the EML in my face again.

Checked the codes, I don't recall seeing anything unusual. Cleared them, called BMW and said I thought a coil pack was buggered again.

They ran a diagnosis and couldn't tell me anything other than the cat has a high sulphurisation. I was a bit pissed, as i'd already told them that fault code seems permanent and hasn't affected the car running since we've had it, not has it flagged the EML. They agreed that if the light came on again, they'd do a diagnosis for free and I agreed to not touch the car!

About 4 months ago, the EML comes up when driving it (only on the large display, not the individual yellow check engine light on the dash cluster). Leave the car parked for a few hours, come back, start it - fine. No light, nothing.

Nothing happens for months again until last Sunday.

Saturday - all day, fine. Sunday morning - EML (the large graphical display and the dash cluster one), idling issues, whole car is shaking like it's misfiring, engine is shaking around in the bay, the works. Again, once the revs are up and your driving it, feels no different to normal.

Started the car again twice during the course of Sunday to see if it was going to miraculously fix itself. It didn't. Yellow dash engine light still on.Engine sounds like it's running fine though.

Called BMW on Monday, booked in for today at lunchtime.

Swapped the cars around on the drive this morning. Yellow dash EML still on, engine running fine.

The leave 4 hours later to take it to BMW, and bugger me, no lights, no warnings, engine's running fine.

BMW obviously don't have a scooby what's going on, all they can report is that the only fault stored is the bloody cat high sulphurisation.

Now, this is odd, not only because there were no other faults stored, not even the thermostat, but whatever was causing the car to look like it was having the automotive equivalent of an epileptic fit on Sunday has not been stored.

BMW suggest I spunk £700 odd on a new cat, which I'm not convinced about because in my head (and from previous exprience on an RX8) when the cat is clogged, it's clogged 24/7. It's not clogged one day, perfectly fine for months on end, clogged again, fine...etc.

I'm at a loss.

So, a few questions.

Does a faulty cam sensor not flag the EML?

I've read about the VANOS solenoids getting gummed up - which in turn can give a cam sensor fault, when its' not actually at fault. Again, this would flag the EML and be stored as a fault though, no?

The car has done a lot of miles for a 57 plate - it's on 102k, so it's not like it's jsut done pissy little journeys around town all it's life. It was a corporate sales reps car before we owned it, so it's done it's fair share of motorway miles - and I alternate between mine and this one to make sure it gets a good run (usually around 100-200 mile round trips) during the week - so it's not like it's not getting heated up to do a regen cycle.

I'm tempted to use some seafoam to see if it'll help clear the cat (assuming that it does need clearing) - anyone used it on their car? I've used it on the RX8 to good effect.

Honestly, so daft that there's no traceable fault. The car was purring away today on the way home, perfectly happy with life.

I'm seriously starting to wonder if there is some truth in the rumours that the BMW electronics are sensitive to cold, damp weather - as it seems very coincidental.

[jotty]

Id be tempted to go down the faulty sensor route, like you i have had all the coil packs etc done with no issues in last 2 months until Sunday when for no reason the EML came on and the red oil light.
Checked everything and couldn't find a problem. My neighbour restores old cars and he said that the damp weather is to blame, so I got out the wd40 and sprayed the relevant bits and had nothing since.

[Mikex101]

I had a load of issues with mine, stalling while driving, rattles, EMl's etc and it turned out to be water in the ECU. Take the ECU out and check for water damage.

[Russbmw]

Remind me where it is on the e9x? Is it by the engine bay bulkhead?

[cage911]

I had similar issues with my car. Turned out to be the fuel injectors needed replacing. Poor running due fuelling issue will cause high sulphurisation in the CATS. Hence why BMW always seem to diagnose the CAT or NOX sensor needs replacing.

Do you do a lot of around time driving?

[Russbmw]

It's always done a mixture of town and motorway to be honest, because I'm of the old school of thought that always driving your car short distances so it doesn't get chance to warm up isn't a good idea, so I try use if for some of my work trips as well, to give it some long runs.

Just been out in it this morning actually, and it's been fine.....as usual....I doubt I'll see that elm for another few on the now.

Fucking thing.

[poggy]

Could simply be a loose/corroded/water affected connection somewhere.

[Mikex101]

Originally Posted by Russbmw

Remind me where it is on the e9x? Is it by the engine bay bulkhead?

Yeah, Behind nearside suspension strut.

Need to remove the scuttle to gain access to it.

[grimwood1992]

just out of curiosity russ did you ever find out what this was?

[Russbmw]

Originally Posted by grimwood1992

just out of curiosity russ did you ever find out what this was?

No mate.