Well for the second time in less than 2 years I have experienced the engine cranking but not starting problem. The last time this occurred it went back to my local BMW dealer under their AUC warranty on the back of a transporter for which their diagnosis was a duff battery.
Since then I have had no problems whatsoever until today. What makes it worse is that I was going to use the car 2 hours after it sailed through its MOT test with no advisories and which included a 30 mile journey.
What was interesting this time was when starting the engine it instantaneously started and then hesitated as though the fuel wasn’t getting through. It then went into a continuous crank with out starting the engine.
Because I had to be some where quickly I used another car and was back within half an hour.
I then gave it another go. The car just kept cranking but I pushed down on the accelerator slowly and it started. The engine emission light was on for a little bit longer than normal but eventually disappeared.
I’ve started the car a couple of time since and there’s been no problems.
I always thought that this problem was related to fuel flooding but I am not so sure now………More like restricted or no fuel flow…...
I ve seen others on the forum have commented on fuel filters and pump relays…..I was wondering whether these two items are simple DIY replacements or if anyone has ever changed them.
I’d thought I’d got over the uncertainty of weather the car would start or not but now I’m back to square one…………Oh the joys of owing an X5……Don’t you just love it………
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4.8is Turns Over But Wont Start (Again)
4.8is Turns Over But Wont Start (Again)
2005 4.8iS Carbon Black
4.8is Turns Over But Wont Start (Again)
[quote=""Ricko""]
I ve seen others on the forum have commented on fuel filters and pump relays…..I was wondering whether these two items are simple DIY replacements or if anyone has ever changed them.
[/quote]
Sorry to hear if your problems starting the car. As I was reading I was saying to myself 'fuel relay' and I think you are right with it as the most possible diagnosis. I think you can get a relay for circa £10 and fitting is a straight forward swap.
Hope you get it sorted asap.
Good luck
Sent from my iPod device using Tapatalk
I ve seen others on the forum have commented on fuel filters and pump relays…..I was wondering whether these two items are simple DIY replacements or if anyone has ever changed them.
[/quote]
Sorry to hear if your problems starting the car. As I was reading I was saying to myself 'fuel relay' and I think you are right with it as the most possible diagnosis. I think you can get a relay for circa £10 and fitting is a straight forward swap.
Hope you get it sorted asap.
Good luck
Sent from my iPod device using Tapatalk
3.0d Sport Exclusive E53 CB with black comfort, pano, folding dimming mirrors, 20"ers, comms, xenons, focal sub, Intravee II, GSM heater........and so on.
Runabout - E92 3 Series Coupe
Runabout - E92 3 Series Coupe
4.8is Turns Over But Wont Start (Again)
Sounds like the same issue I had, turned out to be the pre fuel pump relay which can be had from the stealers for £10 and is a 10 min job to fit, located behind the glove box.
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Re: 4.8is Turns Over But Wont Start (Again)
You might recall my having a similar issue with my 4.8 - both times the car had run perfectly only a short while before. First time the recovery chap from BMW Emergency sprayed some stuff into the air intake and it started up again - heavy petrol smell, like it had flooded. Had it into BMW Main dealer after that - no fault codes stored so they stated they could do nothing!! It ran perfectly after that, even when the oil coller popped its cloggs there was no issue starting. Then a few weeks ago, drove about 30 miles, parked and went to a meeting, came back and it wouldn't start - just cranked away endlessly. Called BMW Emergency again, this time chap said he couldn't use the spray as they had been told the cars become "addicted" to it (!!!) - he twiddled the gear lever up and down a few times and claimed that a sensor was sometimes at fault and the car "thought" it wasn't in park (!!!) - but it started up again no problem and fingers crossed its ok but I'm left wondering WHY? No fault codes again........ I absolutely love the car, but there's just a little hint of doubt about reliability with this sort of peculiar issue 
X5 2005 Le Mans Blue 4.8is
Fully loaded but Now semi-retired!
X5 2012 Alpine White 40d MSport 21" style 215 black alloys, rear entertainment, media package, comfort seats and a load of other options.
Fully loaded but Now semi-retired!
X5 2012 Alpine White 40d MSport 21" style 215 black alloys, rear entertainment, media package, comfort seats and a load of other options.
Re: 4.8is Turns Over But Wont Start (Again)
Are you getting any smoke/exhaust fumes coming from the engine bay??
54 PLATE E53 3.0d X5 FACELIFT BLACK WITH BLACK
Re: 4.8is Turns Over But Wont Start (Again)
I didn't have, no, although Ricko might have had. If its a relay then why does it work perfectly 99% of the time? Surely if its duff then its duff and the car won't start? Also, would a bad relay not show up as a Fault Code? My 4.8 had no stored fault codes for either of the occasions when it did this to me.
X5 2005 Le Mans Blue 4.8is
Fully loaded but Now semi-retired!
X5 2012 Alpine White 40d MSport 21" style 215 black alloys, rear entertainment, media package, comfort seats and a load of other options.
Fully loaded but Now semi-retired!
X5 2012 Alpine White 40d MSport 21" style 215 black alloys, rear entertainment, media package, comfort seats and a load of other options.
Re: 4.8is Turns Over But Wont Start (Again)
Cheers for responses…………
No smoke or fumes from engine bay…………Although it did smell a bit of petrol after it started……….I’ve had no problems since.
I would like to think that it would have been something obvious like a relay but working in an electro mechanical field and as Condor X5 said relays normally either work or they don’t.
Mind you that’s not to say that what energises the relay may be causing a problem particularly as the majority of faults on cars are electrical.
I am going to try and get hold of a wiring diagram for the fuel pump circuit just to satisfy my own curiosity. The problem I experienced was definitely fuel starvation.
It may be possible to carry out some basic testing if it happens again assuming that you can get to the areas that need testing…….Probably a bit of wishful thinking there on my part..........
When my car went in to BMW on the transporter no fault codes were found and I was never entirely convinced that it was down to a duff battery. If an intermittent fault doesn’t raise a fault code there’s no way BMW will find out what the problem is as they can’t and won’t think outside the box…..
I will remember the comments about moving the gear select to different positions……….On outpost some of the forum members there have pinned it down to the ignition switch, the immobiliser or engine management software. Might be worth just getting out of the car……..Locking it, setting the alarm , unlocking then trying again……..
One of the more prolific members mentions an obsolete technical service bulletin relating to the fuel rail. Others have asked about this but there seems to be no record of it.
I have been lucky so far as every time this has happened it has been on the drive. I extended my AUC warranty last year and it’s nearly up. I don’t know if it’s offered again but with things like this happening I’ll probably extend it for another year if I can.
No smoke or fumes from engine bay…………Although it did smell a bit of petrol after it started……….I’ve had no problems since.
I would like to think that it would have been something obvious like a relay but working in an electro mechanical field and as Condor X5 said relays normally either work or they don’t.
Mind you that’s not to say that what energises the relay may be causing a problem particularly as the majority of faults on cars are electrical.
I am going to try and get hold of a wiring diagram for the fuel pump circuit just to satisfy my own curiosity. The problem I experienced was definitely fuel starvation.
It may be possible to carry out some basic testing if it happens again assuming that you can get to the areas that need testing…….Probably a bit of wishful thinking there on my part..........
When my car went in to BMW on the transporter no fault codes were found and I was never entirely convinced that it was down to a duff battery. If an intermittent fault doesn’t raise a fault code there’s no way BMW will find out what the problem is as they can’t and won’t think outside the box…..
I will remember the comments about moving the gear select to different positions……….On outpost some of the forum members there have pinned it down to the ignition switch, the immobiliser or engine management software. Might be worth just getting out of the car……..Locking it, setting the alarm , unlocking then trying again……..
One of the more prolific members mentions an obsolete technical service bulletin relating to the fuel rail. Others have asked about this but there seems to be no record of it.
I have been lucky so far as every time this has happened it has been on the drive. I extended my AUC warranty last year and it’s nearly up. I don’t know if it’s offered again but with things like this happening I’ll probably extend it for another year if I can.
2005 4.8iS Carbon Black
Re: 4.8is Turns Over But Wont Start (Again)
[quote=""Ricko""]Cheers for responses…………
No smoke or fumes from engine bay…………Although it did smell a bit of petrol after it started……….I’ve had no problems since.
I would like to think that it would have been something obvious like a relay but working in an electro mechanical field and as Condor X5 said relays normally either work or they don’t.
Mind you that’s not to say that what energises the relay may be causing a problem particularly as the majority of faults on cars are electrical.
[/quote]
Having worked in a similar field (as so to speak as I am not a field worker- I know what you lot can be like
) I would disagree in that too many times I have experienced faulty relays.
If you have a burnt contact, It may spark through most of the time but contaminants will buid up and in the end they will insulate the contact points. After multiple operations the debris is knocked off and the process starts all over again - for a while.
Also, if the relay has been overheated in some way, the contacts (presuming more than single pole) can become missaligned and not 'make' at the same time/efficently.
Then there is the coil, maybe it's breaking down and not always doing its job, also the flywheel control may be compromised.
Unless the BMW software was to monitor and log every low fuel pressure incident with a non-start scenario (I doubt it is that good) then I would be supprised if it did show any faults.
So if in any doubt, I would change it out and hopefully sort the problem, if not it will elliminate one element for a reasonably low price.
This is of course just my opinion, so please feel free to ignor
No smoke or fumes from engine bay…………Although it did smell a bit of petrol after it started……….I’ve had no problems since.
I would like to think that it would have been something obvious like a relay but working in an electro mechanical field and as Condor X5 said relays normally either work or they don’t.
Mind you that’s not to say that what energises the relay may be causing a problem particularly as the majority of faults on cars are electrical.
[/quote]
Having worked in a similar field (as so to speak as I am not a field worker- I know what you lot can be like
) I would disagree in that too many times I have experienced faulty relays.If you have a burnt contact, It may spark through most of the time but contaminants will buid up and in the end they will insulate the contact points. After multiple operations the debris is knocked off and the process starts all over again - for a while.
Also, if the relay has been overheated in some way, the contacts (presuming more than single pole) can become missaligned and not 'make' at the same time/efficently.
Then there is the coil, maybe it's breaking down and not always doing its job, also the flywheel control may be compromised.
Unless the BMW software was to monitor and log every low fuel pressure incident with a non-start scenario (I doubt it is that good) then I would be supprised if it did show any faults.
So if in any doubt, I would change it out and hopefully sort the problem, if not it will elliminate one element for a reasonably low price.
This is of course just my opinion, so please feel free to ignor
3.0d Sport Exclusive E53 CB with black comfort, pano, folding dimming mirrors, 20"ers, comms, xenons, focal sub, Intravee II, GSM heater........and so on.
Runabout - E92 3 Series Coupe
Runabout - E92 3 Series Coupe