2006 X5 Diesel intermittent cold start problem

[X-ray Lima]

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

My '05 diesel has started playing the same game.

Yay.......

[Gregory891]

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).

[X-ray Lima]

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

Thanks though!!

[opienor]

Originally Posted by X-ray Lima

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

My '05 diesel has started playing the same game.

Yay.......

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!

[X-ray Lima]

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.

[omodos]

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

[X-ray Lima]

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

[omodos]

Originally Posted by X-ray Lima

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

[srmmmm]

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

[omodos]

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....