Engine turning off/stalling at any speed, without warning...

[RossC]

On Friday, while travelling at 60mph on the A9 I felt a tiny hesitation on the engine, nothing to worry about but it was definitely a momentary blip. Later, on a separate journey it stalled at very low speed. Restarted and further 30 miles travelled without issue.

Thought I’d treat it yesterday to some injector cleaner with its usual fill up of BP Ultimate Diesel, and take it for a blast. Once engine was up to temp, while sitting at around 2k revs, engine simply turned off and I coasted in to a lay-by. Engine starts without issue and idles fine but stalls soon after. A couple more miles here and there, but soon realised, engine is fine when cold, but once warm, it will simply turn off at any speed without warning.

Wasn’t going anywhere fast so got the RAC to shadow me home. As I waited for them on the verge for over an hour, I knew the car would start and get me home without issue while Mr RAC followed.

Whole time going through my head was injectors, but no warning lights whatsoever - genuinely just feels as if someone is pressing the off button, just as it did on that one occasion yesterday.

RAC diagnostics showed faults on all glow plugs and controller (never had any starting issues at all) and some low battery voltage warnings (I assume historical after lockdown). There was an unknown error code, (42FB), but by selecting it, it seemed to suggest injectors 2 and 8.

I’m convinced in the cold weather I’ve started to hear the EGR solenoid knocking away on cold starts, but I can’t imagine the EGR shutting the engine down at decent revs, but then I didn’t expect that of injectors at high revs either, perhaps more of a lumpy misfire..?

What do you reckon? Mr RAC reckons when the Audi injector thing was around, they were identical in symptoms, but EML would come on - he was puzzled by the lack of warning lights.

2009 E70 X5 3.0SD (35d)



Battery definitely seemed like the likely candidate this morning - had to input the time in to the idrive after charging for 3hrs.

Took it for a short run - all good. Came home, gave it another 2hrs of charge.

Short run, but got it more up to temp, and turned off on me in the middle of a roundabout. Managed to get it in to the exit for the local Tesco. Restarted and got it a few more metres in to a lay-by.

Let it cool for 30 minutes. Started twice no bother, but will no longer idle. Just cuts out.

I’ve walked home and will return to it tonight to see if I can get it home.

With the help and advice of some friends, I was absolutely convinced of battery, now, not so sure.

Perhaps someone can offer some advice before I contact my local Indy tomorrow?

Thanks for any suggestions.

[X5Sport]

Looks like you need all 6 glow plugs and the controller too (a common issue). Losing all 6 will prevent the DPF from regenerating and it will clog. Glow plug faults do not trigger warning lights. Changing the plugs needs care as they can bind and snap as happened to me a year or so back. That alone was an £800 repair at an Indy. Plugs are about £30 each and about £80 for the controller (BERU). Plugs failures usually kill the controller too.

The others all seem to be indicating electrical problems of some sort so the battery has to be a good place to start looking. A fully charged battery could clear them. Once reset after a full charge see what codes reappear.

The batteries on these cars do not like ever going flat as it shortens their service life significantly. Anything over 6 years old is either doing very well, or about to give up.. The standard is an AGM type, 110 format. It needs coding to the car or it will not charge correctly due to the Intelligent Battery System needing to know a new battery has been fitted. A dying battery will only give a warning about excess discharge on the iDrive.

The brake wear sensor should definitely trigger a light. That needs investigating. They are ‘single-shot’ devices and must be replaced if triggered. Has a previous owner disabled something? It might be low voltage related, but that doesn’t seem right.

I’ve never heard of an EGR issue shutting down an engine.

A dead battery will need at least 8-12 hours to recharge (I use a 10A CTEK Conditioner) and if an AGM type fitted, the right type of charger as the charging cycle and voltages are different for AGM (14.4V DC) than for conventional Lead/Acid wet batteries (13.8V DC).

Error code 42fb is connected with the fuel injection system itself (and again no warning light!) and from a web search indicates injector failure causing the engine to cut out, specifically when warm. Use of the BMW diagnostics will identify which injectors for certain, but it looks like you have those. My search indicates that you may need them replacing depending upon the specific tests to check activation voltage and resistance data (via diagnostics). Generic readers either don’t identity or misread these codes. If your Indy has a copy of INPA (BMWs diagnostics) that will help

[RossC]

Thanks for your comprehensive reply.

I'm viewing most diagnosis points as red herrings as not many seem applicable. No issues starting so I had already discounted glow plugs, and I know how these batteries like to throw a spurious code or two when low. No issues with brake sensors either - I changed the pads myself a while ago and all sensors were fine.

There are no dash errors to speak of, so that in turn brings me back to the injectors. You certainly makes sense of the 4FB2 code, injector failure while warm sounds exactly right.

In that case, I'll stop chasing the battery (it's only 1yr old and was coded) and phone my indy tomorrow. He's absolutely brilliant, but sadly always has a waiting list of 2 weeks or so

[X5Sport]

Try a code reset in case some of them are historic and will clear. Given most are connected with battery undervolts that could just be the usual BMW scaremongering! If they come back then look again.

The brake sensor one sounds just like one of those given you changed everything so it may be just historic - especially with no warning light.

The glow plugs only work below 5°C downwards from memory, so you probably won’t see a difference at present given how warm this month has been to date. This coming week is going to be a bit colder though - assuming the Met Office are to be believed.

The search on that code implied a short to ground when hot. I can imagine a ‘self-protect’ mode then causing a shutdown, but it should still bring up a warning IMHO to at least warn the driver! Not doing so sounds like dangerous design to me.

[Alan Gunn]

I would let a good local indi do the glow plugs and controller and get them to do a proper bmw code scan.
Wouldn't trust the RAC scanner after it suggested injectors 2 and 8 in a 6 cylinder engine.

[RossC]

...but it should still bring up a warning IMHO to at least warn the driver! Not doing so sounds like dangerous design to me.

It's a pretty terrifying experience, I can tell you.

Spoke to my independent this morning and immediately he said over the phone it’d be injectors 5 and 6 getting wet.

Still took it down to him for proper diagnosis before shelling out on the parts though.

Codes showing injector 4/5/6 but as they share the same wiring, in his experience, he reckons it’s just injector 5. Also recommended getting the glow plugs and controller swapped out at the same time.

Biggest problem, he can’t do it until December, and even then, he doesn’t really want to do it.

Looks like it will be off the road for the foreseeable

[X5Sport]

At least you have it narrowed down. Damp would cause a short to ground

I can see why he doesn’t want to do the plugs. Too many snap and it’s a pain to sort BUT should the worst happen it isn’t an engine apart job. I paid for the Indi to get a special kit (about £50) that recovers the parts. BMW don’t use any lubricant and this is the issue, they stick in place. On replacement my Indi used a high temp ceramic grease that should make it easier to remove them next time.

In your unplanned downtime, you could start putting a bit of WD40 Fast Release Agent (not normal WD40) or a similar release agent onto the top of the plugs few days before. It might stop any sticking. BMW use a special fluid but with newtis having gone down I can’t find the part code.

[pcdee]

I have a similar issue with mine at the moment, mine turns off as soon as I turn it on and go. If I wait for 30 seconds its fine, I ran Carly through it and it comes up as injector 5, glow plug 3 and 6.

I've got the glow plugs and control coming tomorrow and the injectors are still under warranty as they were done last year.

Will keep you guys posted.

[Leslie]

Wonder why its always injector 5 , you would think it would be unlikely to get wet with the engine top cover on

[RossC]

I was going to buy the Beru plugs and 2x Bosch injectors from eurocarparts - can’t seem to find the glow plug controller though.

Any recommendations for a parts supplier that will do all? Or indeed, if the controller is hiding somewhere in the website..?

After all the silly discounts and exchange rebates, probably looking around £270 for 1x injector. Does that sound right? I note GSF (before discount) want upwards of £800 for one (premium) injector

[pcdee]

I bought bosch plugs and beru controller from ebay for £120.

https://www.ebay.co.uk/itm/FOR-BMW-X3-E ... 2749.l2649

[X5Sport]

Carparts4less is Eurocarparts but without the shop so cheaper as long as you can wait for postal delivery

[Alan Gunn]

I had 2 injectors changed by my local bmw indi and the total cost was £485 well around that.
That covered the leak-off test parts and labour.