2006 X5 Diesel intermittent cold start problem
 

Hi guys!

Well I´ve understood I´m not the only one with X5 start problems...
Never had any problems with my car, but a couple of weeks ago I started having problems starting it. It seems that the colder it gets outside the more pronounced the problem is. Here´s what happens:
I turn the key and all is fine. Everything lights up as usual and the DDE light indicates glowing. Then starter cranks just fine but there is no sign of ignition. I then have to completely turn the ignition off and try many more times before the engine suddenly fires.
I notice that every time the engine fires there is an extra pump buzzing sound when I engage the ignition. Hence it appears that the diesel pump fails to function every now and then. But what causes this? My car is at an official BMW dealer as we speak but they haven´t been able to recreate the problem and have no clues. The outside temperature is of course much higher now, so the problem doesn´t show up. Needless to say I´m getting a bit frustrated. Any ideas much appreciated!!:thumbup:

[QUOTE=opienor;812122]Hi guys!

.................. the DDE light indicates glowing. QUOTE]

Whats the outside temperature when this happens?Does the glow plugs light stay on while you are cranking ?
Do you have any error codes?
From a mechanical side,they shoud be looking at glow plugs first,injectors and then they should check the fuel pump pressure.

From an electrical side,they should check the crank sensor,fuel rail pressure sensor .

Thanks powers1!

The problem gradually intensifies as outside temperatures drop. Lower temps equal more start attempts. Worst case happended at -4 deg. Fahrenheit when the engine just wouldn´t start at all and the car had to be towed. I´d say the problem appears between approx. -4 to 23 degrees F.
I think you may be right about this being some sort of a sensor or electronics related problem. Especially since I can clearly hear that the fuel pump fails to activate the times the car doesn´t start. Something appears to be wrong in the startup sequence. I glow, fail to hear the pump, crank with no start. This is repeated a number of times until the pump (I assume) suddenly comes to life when ignition is activated, the glow light goes out and voila the engine starts. I have tried to go from off to ignition without cranking a number of times to see if the pump suddenly starts, but without any luck. The cranking (without start) somehow seems to "wake up" the pump for the next start attempt.
The glow indicator lights up and then goes out before I start cranking. Everything appears normal in that department. And no error codes I´m afraid.

Well,its when you dont get the error codes ,and the engine doesnt start,that the hard work starts:(
Have you tried waiting 25 secs before cranking the engine?This is about the time the glow plugs take to turn off and will give you more heat to burn the diesel and start the car.
The coolant sensor is also influencial in the start procedure,so get them to have a look at that.
Another thing is if your EGR valve is closed ,it wont allow air into your engine and it will starve and wont start.To test it,You can pull off the vacuum pipe to it and see if it makes a difference.
The best way and we do here is we do it by trial and error,by replacing the sensors I mentioned above.
Today ,we had a 330d E60 that wouldnt go above 2500 rpm when the engine coolant temp (ECT) was between 10-50 degrees...!After this temp, it was fine!No error codes !We replaced the obvious sensors...nothing!Tried the turbo solenoid and voilá...all good...:dunno:
I leave you here a pic of all the sensors in the engine compartment.

Haven´t tried that but will do. Does this glow period change with temperature or is it a standard 25 secs regardless? I didn´t know the glowing lasted that long. Always thought glowing stopped when light goes out. Thanks for teaching:thumbup:
With temps going way below zero F here in Norway during winter most diesel cars have a hard time every now and then. Mostly caused by dirty, clogged up and frozen fuel filters. Initially thought to be the problem with my car, but no.
The BMW guys continue their little investigation on my car tomorrow so crossing my fingers they will discover the reason. In the mean time my trusty 318i runs like a clock:cool:

Thanks a lot for taking the time powers1

Its not temperature related!Glow plugs go out when the Glow plug module switches off (about 25 secs) or when you crank the engine,whichever happens first.
Normally,when the plugs are going faulty,letting them be on for a few more secs,helps them heat-up more.This is also a sign that they need changing as they are either taking longer to heat-up or you have a faulty plug(s).
In anycase ,in extreme below freezing temperatures,its always best to wait a few more secs,before you crank it, after the glow plug light goes out.
Above freezing,they are almost redundant.

I hope the Bmw guys there do their job!
Keep us posted please:thumbup:

So got my car back a few days ago. The mechanics had tried to reproduce the failure to start but it just started and ran like a clock every time. Very strange, although the weather is considerably warmer now so that might be the reason. So no luck on finding the issue.
I´m starting to think there could have been some kind of contamination in the diesel fuel at some point, water that froze or something. Although I can´t see how that would prevent the fuel pump from working during the start sequence.
Oh well just have to wait for next winter and cold weather again to find out I guess. Thanks anyway for trying to help!

Thanks for posting back with feedfback:thumbup:
Although they couldnt replicate the start failure,the important thing is, its now running ok.Lets hope whatever it was it resolved itself and you wont have any more problems:)

So unfortunately I´m back to revive this thread on my 2006 E53 X5. This cold start issue reoccured last winter but didn´t cause too much problems as temperatures were fairly high.
Now winter is back, and so are the problems. Same thing: cranks just fine, but total diesel starvation as the electric feeder pump doesn´t start when engaging the ignition.
Took the car to the mechanics and history repeats itself: car starts like a charm every time (around freezing), glowing works fine, fuel nozzles are fine, battery is fine, no associated error codes. They change the fuel pump relay as it´s a cheap part and could be the issue.
Got the car back yesterday. Today outside temp is -12C and the car doesn´t start. Electric feeder pump kicks in about 1/20 ignition attempts.
So I set out on a little trial and error quest of my own. Suspecting cold/humidity build up in electronic components I use a hairdryer to heat the electronics compartment under the hood up to room temperature. I also give all connections and relays a good "shake" in case there are any bad connections.
After that a new start attempt, but no luck. No feeder pump kicks in.

So I place an electric car heater on top of the engine, close the hood and let the compartment heat up slightly for about 20mins. Still no luck on starting.
As a last resort I move the car heater to the left side of the car (as seen facing forward), blowing hot air downward.
Voila: after a couple minutes the feeder pump now starts up on every ignition attempt. The engine starts at once on several consecutive start attempts.
I don´t know what exact components are located down there on the left, but most noticeable is a square one with five thin metal pipes exiting it forward.

It seems now I may be onto something, but absolutely without knowing exactly what:cool: Not believing my findings I let the engine cool way down again for a couple of hours before repeating this last procedure. Same thing as above: everything works flawlessly after heating the left side for a few minutes.

Any idea what this could be?
This car is now giving me a headache all over again. As much as I love it I´m also getting really frustrated with this issue. It has already this winter ruined one long weekend and several appointments I never got to.

Here is a video of the problem. No buzzing from the electric fuel pump when engaging the ignition. Cranking works fine but engine is totally dried out:

BMW X5 E53 Cold start problem - no start - YouTube

In this second video I have tried starting MANY times (appr. 30) and now sudddenly the electric feeder pump kicks in every time I turn on the ignition. You can hear it buzzing in the background. Engine starts with ease. Today heating the engine compartment seemed to have little or no effect for some reason:

BMW X5 E53 Cold start problem - starting - YouTube

I talked to the dealer today and I´m taking the car back in a week. This time I will let it sit there until the problem is solved. I also sent them these videos.

Did you ever wind up gettin this sorted out???

My '05 diesel has started playing the same game.

Yay.......

On my 2002 X5 (lower 184 PS), my car always starts in cold winter (Switzerland) but it's REALLY important to wait until the DDE light goes out (electric warmup). Failure to do so at -5 to -15 C (about the coldest I've seen here) means she will start, but more cranking to get her going and black smoke when first running. Almost none if you wait for the DDE light to go out (the owners manual advises this as well).

Living in Western Australia, the temps here rarely get below 5 degrees, let alone -5, so I think my problem lies elsewhere!!!

Thanks though!!

I sure did! Meant to update this thread but never got around to doing so.

As stated in my last post the car went back in to the mechanic. It turned out that there was yet another relay also affecting the fuel pump. If I remember correctly this one sits behind the glove box. The mechanic changed it and opened the old one to find the contact surfaces were badly scorched (the other relay he changed earlier looked just fine on the inside by the way).
Evidently the relay worked OK when the air was warm and dry, but the problems kicked in with cold and humidity.
After this the problem was solved. Has started just fine ever since. The dealer only charged me a few bucks for the last relay and not for the job. Seems they were a little embarrassed they didn´t change both relays the first time around. After all I had described the problem to them in great detail.

Best of luck and do let us know how it goes!

Funny you should say that.....

After several hours of googling, I came to the conclusion that particular relay was the most likely (and cheapest) possible culprit for the symptoms.

Since the car played up about 5 times yesterday, I snatched it and went and picked up an OEM relay from BMW stealership and installed it yesterday arvo. My old relay looked a but old and sad too, but have seen worse operate ok.

Fingers crossed its fixed the problem. Started fine this morning and it was cold (for Perth). Another few days will tell the whole story I guess.

X-ray LIma old post, but did this relay replacement sort out your issue?

Hasn't missed a best since swapping the relay out.

Hmmm thanks for the reply, am gonna start with checking my starter motor leads and jumps start points cos i have the same laboured start-worse in the cold weather temps rarely drop below 5c here either!, you do'nt by any chance have the relay part number do you?and is the relay for the fuel pump you say? and was removing the glove box/fuse box easy? to get access to this relay?

thing is i do hear the fuel pump in action before starting but suppose wont do any harm changing a relay...

PLUS if i have used he darn amp clamp correctly the amp draw on my battery when starting engine hits 400amps and over possibly the reason for laboured start-and no idea if this symptom of 400amp plus amp draw is a result of a bad connection on the starter or a bad starter or both...happy days trying to figure this out:rolleyes:

Your 400 amp reading is not unrealistic. The 1981 (yes I know I'm going a little old school here) Bonneville diesel I had - GM 5.7 liter V8 - would pull nearly 500 amps on a cold start. That's why they had two batteries. Each glow plug was a 30 amp draw, and the starter was good for anywhere from 200 to 260 amps depending on temperature and how fresh the oil was in the crankcase. Even though you weren't supposed to engage the starter before the "WAIT" light would go out on the glowplugs, the glowplugs could actually stay energized for up to 20 seconds after that just to make sure there was enough heat to keep the combustion process going. Granted, that engine had a 22.5:1 compression ratio, but diesels take a lot of electrons to get them to turn over when it's cold. I eventually racked up 276,000 miles on that car and admit I sometimes miss the highway ride and 33mpg it had!

2002 X5 3.0 271,100 miles
2004 325i 118,000 miles

Srmmmmmmm appreciate the feedback, and have been trying to do the maths on this based on what the starter is rated at for a 3.0d

It is 2.0kW so it can output up to this 2000watts correct?to achieve this: power 2000=(I)current X the (V)

2000watts=166.667 amps X 12 volts (assuming the battery is at that voltage)

So would you agree that in this case if the starter is drawing more than 166amps on start its a bad thing for the starter as such...this is a tricky one have not found anything online relating to the X5's 'standard' amp draw on starting the engine...alot of US sites tutorial video type things mention no more than 250amps....hmmmmm again thanks for the feedback...am charging up battery off car today fully, and taking it for the 4th load test tomorrow...will see what that comes back with

PS the temps out here aren't low enogh for the glow plugs to kick in either so I can rule that out....

Remember that at lower temps, your battery does not deliver the same amount of power and as the voltage drops during cranking, the amperage draw will increase to make up for it. As for glowplug use, I wouldn't be surprised to learn that they kick in for a few seconds even on a "cool" start. You might try disconnecting them if there is a relay you can take out of the circuit temporarily to be sure you're only seeing the amp draw from the starter.

2002 X5 3.0 271,100 miles
2004 325i 118,000 miles

thanks again fella, point regarding volts drop meaning higher amps draw to make up for this does make sense read somewhere it should not drop to less than 9.6v during crank so say for arguments sake it does drop to this then

to generate the starters 2000watts output it will need to draw about 208amps 208 X 9.6 =2000

Soooooo 208amps max draw on start, and any lower than 9.6v on crank well I doubt it will crank over....I will dig further around aregarding glowplugs and am waiting for a fella in the uk with the same issue as me to get his looked at tomorrow and get starter replaced....we shall see, thanks for replies

thanks again fella, point regarding volts drop meaning higher amps draw to make up for this does make sense read somewhere it should not drop to less than 9.6v during crank so say for arguments sake it does drop to this then

to generate the starters 2000watts output it will need to draw about 208amps 208 X 9.6 =2000

Soooooo 208amps max draw on start, and any lower than 9.6v on crank well I doubt it will crank over....I will dig further around aregarding glowplugs and am waiting for a fella in the uk with the same issue as me to get his looked at tomorrow and get starter replaced....we shall see, thanks for replies

Same crank but no start issue
 

I've had exactly the same symptoms on a E53 X5 getting gradually worse over the winter months but clearing up in the summer.
Changed the Fuel Pump relay above the fuse board yesterday, came out to the coldest morning of the year so far and it fired up first time, without hesitation. For the sake of a few£ relay and half hour of my time, I was well happy :rofl: