cutting out/stall

[norseman]

Hi guys

Returning home this evening my early (pre 9/98) 523i auto cut out as I pulled up outside the home, prior to my reversing onto the drive & took several cranks to re-start.

This has never happened in the 5 years of my ownership, there is ample fuel in the tank & the 3 year old HD Bosch battery is fully charged. The only clue might be that the crankshaft position sensor (pulse generator on OEM) was renewed by my local garage last week but even prior to that, despite the faulty old unit causing regular starting problems, the current stalling issue wasn't one of them. My other half reported the same 'stalling' at a roundabout earlier in the day, though the car runs without fault whether cruising or under power.

I'll get my local garage to put a code reader on the car ASAP but meantime I'd appreciate anybody's thoughts on the issue. 

[duncan-uk]

Did you do both crank and cam? My 523i would stall and initially i did the cam (as that was the code) but would still occasionally die replacing the crank cured it.

Had odd no start with my 330d and a pair of CPS cured that. in my experience if one goes the other isnt far behind but of course worth checking the plug is seated properly and the new part isnt at fault.

[norseman]

21 hours ago, duncan-uk said:

Did you do both crank and cam? My 523i would stall and initially i did the cam (as that was the code) but would still occasionally die replacing the crank cured it.

Had odd no start with my 330d and a pair of CPS cured that. in my experience if one goes the other isnt far behind but of course worth checking the plug is seated properly and the new part isnt at fault.

Just the crank sensor.

Car now at the garage, hopefully diagnostics will reveal something.

Cheers for the reply, keep you posted.

[duncan-uk]

On my 330d it never threw a code suspect they go intermittent. 

[norseman]

Just what I need .. an intermittent fault 😒

Can't help feeling there is an engine temperature related issue here, daft though that may sound.

Try this for size; car starts immediately when stone cold, drives four miles & is switched off for less than 5 mins. Will then crank but not fire. Leave the bloody thing for an hour & it will fire up as if there's nothing wrong with it.

Drive for 2 miles (bearing in mind that this time the engine had only been standing for 1 hour, not all night as before, then there is a hesitant acceleration moment at a road junction followed by normal driving for the next 2 miles until switched off outside the garage.

I haven't heard back from the garage yet but I'll take a level bet that the car would have started normally when they moved it into the yard at the end of the day.

Edited April 9 by norseman

[4aceman]

Was a genuine crank sensor fitted?

I've found the cam/crank sensors can behave worse when hot than cold. They don't always immediately throw error codes, but eventually they should

[norseman]

5 hours ago, 4aceman said:

Was a genuine crank sensor fitted?

I've found the cam/crank sensors can behave worse when hot than cold. They don't always immediately throw error codes, but eventually they should

Not genuine BM but then where do such 'genuine' parts for long obsolete models come from these days ?  It was a NGK component, chosen on my assumption that it's a well respected brand.

Update 1600hrs. today >

Garage called this afternoon. Twice they had the car running for a long period & after switching off restarts were totally normal. They then took it out for a road test, with the car already hot, then pulled over & switched off, waited a couple of mins. (to emulate my problem yesterday morning) then it re-started first crank, just as it should .. WTF !

Only question remains; it's currently unclear if the mechanic who fitted the new CPS recently cleared the codes on completion of the job. So the code they have pulled up for a faulty CPS could be the original or a new one, something that will be more apparent once the mechanic (currently on holiday) returns to work next week. Meantime my other 'arf & myself will run the car around locally with fingers crossed 😕

Edited April 9 by norseman

[duncan-uk]

8 hours ago, norseman said:

Just what I need .. an intermittent fault 😒

Can't help feeling there is an engine temperature related issue here, daft though that may sound.

Try this for size; car starts immediately when stone cold, drives four miles & is switched off for less than 5 mins. Will then crank but not fire. Leave the bloody thing for an hour & it will fire up as if there's nothing wrong with it.

Drive for 2 miles (bearing in mind that this time the engine had only been standing for 1 hour, not all night as before, then there is a hesitant acceleration moment at a road junction followed by normal driving for the next 2 miles until switched off outside the garage.

I haven't heard back from the garage yet but I'll take a level bet that the car would have started normally when they moved it into the yard at the end of the day.

Exactly what my 330d did, would start fine cold but when warm would crank and not fire untill cooled. No codes where ever thrown but a pari of genuine cam and crank sensors cured it and never happened again - suspect i didnt get a misfire as it was diesel rather than petrol.

[Dbcrd]

18 hours ago, norseman said:

Not genuine BM but then where do such 'genuine' parts for long obsolete models come from these days ?  It was a NGK component, chosen on my assumption that it's a well respected brand.

Crank and cam sensors are one of the few things where only genuine or the orginal supplier to BMW work reliably.  For these it is generally understood that BMW got them fromeither Siemens / VDO now part of Continental. 

At least that is what was reported many times on the "old" forum, as far as I can recall.  You might find the same reports on the other BMW forums. Here is an example:

https://www.bimmerforums.com/forum/showthread.php?2209561-non-genuine-bmw-camshaft-position-sensor-any-experience

As an aside, there is a similar thing for oil level sensor.  Genuine or Hella in that case.

https://www.bimmerforums.com/forum/showthread.php?2209561-non-genuine-bmw-camshaft-position-sensor-any-experience

[norseman]

Thanks for that advice, if needed the next one will be OEM !

Edited April 11 by norseman

[norseman]

Another question on this :

If the 'faulty crank position sensor' code proves turns out to be one flagged up prior to that component's replacement (& not cleared) could a failing/failed camshaft sensor on it's own cause this problem or do the two of them work in conjunction ?

The car's reliability is important but being on a fixed income I'm just trying to avoid paying for the original job to be done twice if there is a viable alterative.

Appreciate your continued help guys. 

[4aceman]

Each code should have a mileage associated with it (stored in KM). INPA does show this information. You should be able to tell if it's a newer code or not

[norseman]

2 hours ago, 4aceman said:

Each code should have a mileage associated with it (stored in KM). INPA does show this information. You should be able to tell if it's a newer code or not

My local garage is not a BMW specialist plus it's now 28 years since the 523i was introduced; I suspect their old-style diagnostics (Snap-On?) that they dust off for the odd occasion that it's needed for such old tech. vehicles will only throw up the basics. Once the mechanic returns next week he will be asked the crucial question.

Many thanks for your input.

[duncan-uk]

Where are you based? Might be someone local with appropriate diag?

[norseman]

Chelmsford Essex.

There is a long established independent  20mins drive from me; why haven't I been to them with this (?) because I like to support my local garage whom I have known for years & being retired means a resolution is not as urgent as it would be for someone who needs their car for work/business.

The mechanic returns to work Mon/Tues so we will then know if that's an old code or not. If they cannot sort the problem I will revert to the independents for a resolution. 

Fortunately I have another car to use if this issue drags on.

Thanks for your continued interest Duncan. 

[duncan-uk]

Any news on this?

[norseman]

Sorry Duncan, missed your post.

Still some confusion about the codes & the garage being stacked out with work doesn't make for rapid advancement !

Latest is that I have ordered both genuine crank & camshaft position sensors from Cotswold to replace the aftermarket products the garage has fitted. The new parts should be here early this week, so once fitted the codes can be read again & hopefully the problem solved. Last resort is to get the car to a BM indie. who should have more definitive diagnostics & will be aware that genuine components have been installed.

Yes I know that maybe I should have gone the indie. route from the outset but I like to support a local business that I have used for years & we do have alternative transport whilst the BM is off the road. Also it was my choice to go for aftermarket parts & thought NGK & Meyle would be up to the job 🤔

[norseman]

Update :

Genuine BM sensors x2 fitted this morning, garage cleared codes prior to installation & report no codes flagged up afterwards or following a road test & prolonged period of idling.

Collected car this afternoon & will be doing a longer journey tomorrow to see how it goes .. everything crossed !!

Now to see if I can return the aftermarket items, if not I'll have to swallow.

Update (2)

After a couple of runs the car seems fine so a good, if expensive, result.

Return excepted for the aftermarket crank sensor, I'll not return the cam sensor as there was no fault shown on the scanner so I've probably wasted £100+ there, but at least I know it's been replaced with a BM part.

Edited May 3 by norseman