BMW E90 BAttery & Glow Plugs

Aurellia

I Know the battery is going on my BMW from reading forums, rang our main dealer to price a replacement, he said bring it in he'd check first. I do that and they said Yes its the battery, also your glow plugs and a preheating box, and that will be €70!!

Ok can you give me the estimate then and i'll discuss with my DH? Ouch, €570 for a parts plus labour and VAT
It's an 2008 and we have in the last while being using our brilliant Latvian mechanic, and not main dealer.
Who tells me- January is always battery problem month especially after Christmas,but the battery is 8 years old !
He says i do not need a BMW OEM battery but can get a compatable one and i can just change the battery and its up to me if i want to do the diagnostics and recode car that new battery fitted.
He also said that i do not have to change the glow plugs- that we do not live in -15 temperatures.

So i'm at a conumdrum. Conflicting advice from Rip off dealer and too sound mechanic.

What are your thoughts ? Is there someting in start up i should look out for ? report back to you for further adviced ?

bmstuff

Hello,

Dealers are dealers. Their overhead are far greater than you local mechanic that works from a 400 euros a month premises. They will often always be more expensive than you average mechanic.

Additionally dealers tend to suggest replacing anything that comes up on their diagnostic and sometimes beyond.

Anyways, on the battery, yes a dealer's battery will cost twice as much as the same battery from your local factor. Yuasa batteries from Halfords are excellent and come with a 5 years warranty. Cost is about 115 euros for your car for the 90ah battery

Unless your car has iDrive and or an IBS sensor built-in into the negative lead, then your new battery does not need registration. It may need coding if the rating is different. If your original battery has a 80ah then that's fine, you can get the 90ah safely and no further action required.

On the glow plugs. Faulty glow plugs and glow plug module can affect fuel consumption and engine smoothness. Now if your car is running fine, not rough, no bad fuel consumption, you are still ok.

Glow plugs indeed help the engine to preheat in those cold weather, so if the engine is running fine, you do not need to change them for another while.

But they will cause problems down the line.

IBS Sensor built into the negative leave connecting the battery negative to the car chassis

Toyotafanboi

Why the neccessity for that IBS sensor, what is it's function? Was there no design alternative to it or is it simply to make battery replacements main dealer only?

ezra_

Toyotafanboi wrote: »

Why the neccessity for that IBS sensor, what is it's function? Was there no design alternative to it or is it simply to make battery replacements main dealer only?

Can't Indie's with the right computer sort this?

bmstuff

Toyotafanboi wrote: »

Why the neccessity for that IBS sensor, what is it's function? Was there no design alternative to it or is it simply to make battery replacements main dealer only?

http://atlanticmotorcar.com/bmw-ibs-intelligent-battery-sensor-what-is-it-what-does-it-do/

bmstuff

ezra_ wrote: »

Can't Indie's with the right computer sort this?

Yes sure plenty can, with the right equipment. Lots of diagnostic solutions are able to register batteries.

If you do not register a new battery, when necessary, then the car thinks you still have the old one and will therefore overcharge it.

This can result in 2 things potentially :

- Will reduce the lifespan of the battery to 2-3 years instead of 6-7 on average
- May cause battery explosion (This has been seen and documented a few times)

enumbers

bmstuff wrote: »

Yes sure plenty can, with the right equipment. Lots of diagnostic solutions are able to register batteries.

If you do not register a new battery, when necessary, then the car thinks you still have the old one and will therefore overcharge it.

This can result in 2 things potentially :

- Will reduce the lifespan of the battery to 2-3 years instead of 6-7 on average
- May cause battery explosion (This has been seen and documented a few times)

Would love some links to information supporting the last bit if you have any for my own education purposes
Regards

bmstuff

enumbers wrote: »

Would love some links to information supporting the last bit if you have any for my own education purposes
Regards

Sure you can use google. I came across a few before

The Bishop Basher

bmstuff wrote: »

On the glow plugs. Faulty glow plugs and glow plug module can affect fuel consumption and engine smoothness. Now if your car is running fine, not rough, no bad fuel consumption, you are still ok.

Glow plugs indeed help the engine to preheat in those cold weather, so if the engine is running fine, you do not need to change them for another while.

But they will cause problems down the line.

Just interested to know how the glow plugs will cause problems down the line ?

Reason I ask is that I currently have 4 faulty plugs and have been battling MPG and performance issues.

Seems all is running well again now following replacement MAF, Filter and EGR but the glow plugs are playing on my mind..

As I understood it, they are only used for cold starts and have little or no function once the engine is running. Is this not the case ?

bmstuff

Swanner wrote: »

Just interested to know how the glow plugs will cause problems down the line ?

Reason I ask is that I currently have 4 faulty plugs and have been battling MPG and performance issues.

Seems all is running well again now following replacement MAF, Filter and EGR but the glow plugs are playing on my mind..

As I understood it, they are only used for cold starts and have little or no function once the engine is running. Is this not the case ?

Modern diesel engines use the glow plugs to measure combustion pressure etc. The glow plugs have an extra sensor built-in to achieve that. They act as oxygen sensors in a way if you want. Without the info, engine are not running smooth and diesel consumption goes up.

Aurellia

Ok very helpful.

Can i ask am i supposed to open the boot and look and see what the battery looks like and if the IBS sensor attached to battery?

It's a 320 D M Sport edition UK Origin. It has the iDrive, which funny enough is not working, so i can't reset Tyre pressure, but i think this is down to the battery. We did the timing chain when we got it and all the other necessary bits and the engine to my ear, and feel is running smooth. However i did observe it takes the lights a few seconds to go off on the dash after starting up.
Current mileage is 149500 miles and when i was commuting i was getting 600+/- miles to the tank.

These days it's short runs around town and i work close to house so it sits alot on the driveway or cold start ups for a spin to school and work. I think there lies my problem.

bmstuff

Aurellia wrote: »

Ok very helpful.

Can i ask am i supposed to open the boot and look and see what the battery looks like and if the IBS sensor attached to battery?

It's a 320 D M Sport edition UK Origin. It has the iDrive, which funny enough is not working, so i can't reset Tyre pressure, but i think this is down to the battery. We did the timing chain when we got it and all the other necessary bits and the engine to my ear, and feel is running smooth. However i did observe it takes the lights a few seconds to go off on the dash after starting up.
Current mileage is 149500 miles and when i was commuting i was getting 600+/- miles to the tank.

These days it's short runs around town and i work close to house so it sits alot on the driveway or cold start ups for a spin to school and work. I think there lies my problem.

If you have iDrive then you have the iBS sensor, so not need to get dirty
Driving the car on short distances only is not good for the battery nor for the engine oil.

A faulty IBS sensor could affect the iDrive but also drain the battery. Amongst other potential issues...

enumbers

bmstuff wrote: »

Sure you can use google. I came across a few before

I thought that were the info was coming from ,nothing remotely verifiable that I could find that why I was asking had you any proper info on the subject. Any information I have on the charging system is that not telling the car it has a new battery leads to poor lifespan on the replacement. Its not a big deal to get it programmed in to improve battery life just don t see how its technically possible for it to be the cause of a battery explosion