[a1slam]

Hi All,

I've recently bought a BMW 520i SE (x reg 2001) and have this problem starting the car in the morning. The engine starts shaking as if it is not running on all 6 cylinders along with a screeching noise eminating from under the bonnet. This lasts for ~ 15 to 20 secs and then goes away. The car runs very smoothly thoughtout the day and I do not encounter this problem until the next morning after the car has been left standing overnight. I've inserted a link to a video clip of my cars cold start below. Any ideas on what it could be?

http://www.youtube.com/watch?v=lU4gZj8bceo

Thanks

a1slam

 

[ose1665]

Unfortunatly cannot watch your vid as it's blocked on our system, but the screeching sounds like the drive belt to the alternater, this would be under max load when car is first started as you have just sucked a load out of the battery and it's trying to re-charge it.
With the engine on tick over try switching every electrical item you have on and see if it screeches again.
The shaking could be something entirly different and not connected, some people don't service or have anything checked and as you recently bought it a good service is probably a good idea,
And don't believe the sevice record my E39 said it was serviced by BMW, well I donated my air con filters to Allan Titchmarsh to use as grow bags.

 

[mrbarry]

Another very common problem is the pipes under the power steering reservoir seap fluid very slowly. The belts are oftern soaked in oil and will slip on start up, after a short time the aux devices speed up and the belt surface warms up and grips the pullies better. New belts are very cheap, as are a couple of hose clips to seal the PAS tank If it is this have the front of the engine steam cleaned too, I hate dirty engines :lol

It is very unlikely to be a costly problem anyway!

 

[ose1665]

just managed to watch your vid, sounds like a belt squeeking in with the other noise.

 

[Ronnie]

Do you lose any coolant?

If so it would be a good idea to get a block test done on the car, http://www.uktools.com/product_info.php?products_id=12508.

As for the screech it would be a good idea to check the belt, pulleys, guides and water pump out you could try spraying some lubricant on the belt while it's making the noise to help diagnose if it is indeed the belt.

 

[a1slam]

Do you lose any coolant?

If so it would be a good idea to get a block test done on the car, http://www.uktools.com/product_info.php?products_id=12508.

As for the screech it would be a good idea to check the belt, pulleys, guides and water pump out you could try spraying some lubricant on the belt while it's making the noise to help diagnose if it is indeed the belt.

I've checked the coolant and I am not loosing any.

I took the car to my mechanic who fixed the screech by replacing the drive belt. He said that the rough idle was caused by a leak from one of the ignition coil pencil caps and I got them replaced however the problem still persists. His thinking was that during cold starts there is some dampness around the caps and the electrical leak is bigger causing the rough idle. Is this logical? Next step for me is to leave it with him overnight and let him see the symptons in the morning.

Thanks

 

[ose1665]

Have you checked/changed the plugs, (simple stuff like that), air filter?.
Glad the squeeking has gone, one out of two ain't bad

 

[a1slam]

Have you checked/changed the plugs, (simple stuff like that), air filter?.
Glad the squeeking has gone, one out of two ain't bad

Yes - I had new plugs installed along with the caps. I Haven't done anything about the air filter - Could this cause such a problem?

I am also very glad about the squeeking going but the cold start rough idle issue is much more irritating

 

[Ronnie]

From usual experiences with BMW's, cars that misfire when first started, especially after a long journey are signs of the headgasket weeping. Hence why a block test would be a good idea.

Do you do any/many long journeys?

 

[a1slam]

From usual experiences with BMW's, cars that misfire when first started, especially after a long journey are signs of the headgasket weeping. Hence why a block test would be a good idea.

Do you do any/many long journeys?

I've only done one long journey since I bought the car 2 weeks ago and didn't notice anything throughout the trip or before it other then the cold start issue. My normal trips tend to be very short and within the town

Regards,

a1slam