2008 BMW X3 3.0si N52 slow turn over.

joylove · 05-12-2013, 01:45 AM

Hi there

I have a problem with my N52 engine that I'm hoping someone can help with ideas. I know these E90 forums are way more active than the X3 forums so I'm posting here for help, I hope that's OK.

The car, especially when cold, is very slow to turn over. It turns over like it has a flat battery. Roughly one time in 10 it fails to fire up and you need to retry.

Since I only bought it in November at 98k, I was thinking it needed some 100k service items. It's had

Quality AGM battery (the larger one, car has winter pack)
6*NGK iridium plugs
6*Bosch coil packs
Fresh quality fully synthetic oil and filter
Bosch Air filter
Battery GND fastened

The next maintenance steps I was planning was new O2 sensors. I was also thinking about checking the GND straps to the engine and battery. I'm hoping it's not the starter motor.

The car had full BMW service history and gets used often for short and medium length drives. the Mini parked next to it gets driven less and starts much better.

Are there any N52 issues that might cause a turnover that feels like you have a flat battery?

Thanks.

joylove · 05-12-2013, 02:04 PM

I posted a video of the slow turn over. Some days it's much slower, like a flat battery, but it does start. Feels like there is a slight misfire too when cold, as well as trouble struggling to find the right idle point. This is my wife's main car so I didn't know about the misfire.

EDIT:having watched the video back, sorry the sound is so poor. It's better at starting the second time.

Bimmertech113 · 05-12-2013, 02:10 PM

Put a battery in it

BMDoublYou · 05-12-2013, 02:53 PM

seems like it settles down after the secondary air pump turns off, my dad has a x5 with the N52, big problems with the secondary air pump lines being brittle and cracking, maybe look into those?

joylove · 05-12-2013, 09:08 PM

Bimmertech113> The battery was replaced.

Quote:

Originally Posted by BMDoublYou

seems like it settles down after the secondary air pump turns off, my dad has a x5 with the N52, big problems with the secondary air pump lines being brittle and cracking, maybe look into those?

Thanks, I didn't know that, will check into it. It's the slow start that I can't get any clues on. Admittedly it's not that bad in the video, but it can turn so slowly sometimes that it feels like it's been out in the snow for a week. It's 80F today.

joylove · 01-01-2014, 03:01 PM

It was the starter motor.

Mardio · 01-01-2014, 04:10 PM

Good to know...

joylove · 01-01-2014, 04:30 PM

I found this post unfinished and fought I'd better update it for future visitors to the site.

Seems the N52 starter is a common issue, and most people go to the battery first (understandably) when in fact the starter is (a) gonna fail later and (b) killing the batteries with the massive load (fnar) it puts on.

ssmith96 · 01-01-2014, 05:27 PM

My car does that when its cold it doesn't even seem like that long of a crank to be honest.

joylove · 01-01-2014, 05:34 PM

The length of time and the speed of the crank are two different things though.

One is the fuel pump & the anti-return valve; and the other is the starter.

bmw325i · 01-02-2014, 12:28 AM

Quote:

Originally Posted by joylove

I found this post unfinished and fought I'd better update it for future visitors to the site.

Seems the N52 starter is a common issue, and most people go to the battery first (understandably) when in fact the starter is (a) gonna fail later and (b) killing the batteries with the massive load (fnar) it puts on.

I think I may have to do this soon. I just replaced the battery last week and it is much better, but I still think it starts a little slow.

norsairius · 01-02-2014, 09:47 AM

Quote:

Originally Posted by ssmith96

My car does that when its cold it doesn't even seem like that long of a crank to be honest.

Yeah, I was gonna say, this doesn't seem that bad. My car does a lot worse than that on some of these frigid mornings we've had here lately. I had the dealership look at my car before when it was warmer out and starting like that. They told me nothing was wrong. They've done a good job offering advice to try and prevent the need for service visits too, so I trust them.

joylove · 01-02-2014, 11:53 AM

Mine was slow but ignorable. So I ignored it.

One 100F day I get a call from the wife and it's totally dead. Luckily she could walk home and we got it towed at lunch time.

Mine still needs extra time in the morning to pump the fuel pressure up. Some have added additional anti return valves.

One thing it definitely isn't is slow turnover any more. It turns over like a normal car.

05-12-2013, 01:45 AM	#1
joylove Private 4 Rep 57 Posts Drives: X3 LCI Join Date: Mar 2013 Location: West Coast. iTrader: (0)	2008 BMW X3 3.0si N52 slow turn over. Hi there I have a problem with my N52 engine that I'm hoping someone can help with ideas. I know these E90 forums are way more active than the X3 forums so I'm posting here for help, I hope that's OK. The car, especially when cold, is very slow to turn over. It turns over like it has a flat battery. Roughly one time in 10 it fails to fire up and you need to retry. Since I only bought it in November at 98k, I was thinking it needed some 100k service items. It's had Quality AGM battery (the larger one, car has winter pack) 6NGK iridium plugs 6Bosch coil packs Fresh quality fully synthetic oil and filter Bosch Air filter Battery GND fastened The next maintenance steps I was planning was new O2 sensors. I was also thinking about checking the GND straps to the engine and battery. I'm hoping it's not the starter motor. The car had full BMW service history and gets used often for short and medium length drives. the Mini parked next to it gets driven less and starts much better. Are there any N52 issues that might cause a turnover that feels like you have a flat battery? Thanks.
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05-12-2013, 02:04 PM	#2
joylove Private 4 Rep 57 Posts Drives: X3 LCI Join Date: Mar 2013 Location: West Coast. iTrader: (0)	I posted a video of the slow turn over. Some days it's much slower, like a flat battery, but it does start. Feels like there is a slight misfire too when cold, as well as trouble struggling to find the right idle point. This is my wife's main car so I didn't know about the misfire. EDIT:having watched the video back, sorry the sound is so poor. It's better at starting the second time.
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05-12-2013, 02:10 PM	#3
Bimmertech113 Private 2 Rep 68 Posts Drives: None Join Date: Mar 2013 Location: TN iTrader: (0)	Put a battery in it
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05-12-2013, 02:53 PM	#4
BMDoublYou Captain 117 Rep 622 Posts Drives: 09 E90 335xi / 08 E82 128i Join Date: Nov 2012 Location: True North iTrader: (1)	seems like it settles down after the secondary air pump turns off, my dad has a x5 with the N52, big problems with the secondary air pump lines being brittle and cracking, maybe look into those?
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01-01-2014, 03:01 PM	#6
joylove Private 4 Rep 57 Posts Drives: X3 LCI Join Date: Mar 2013 Location: West Coast. iTrader: (0)	It was the starter motor.
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01-01-2014, 04:10 PM	#7
Mardio Brigadier General 197 Rep 3,211 Posts Drives: 2017 X5 Join Date: Jun 2006 Location: Nashville iTrader: (0)	Good to know...
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01-01-2014, 04:30 PM	#8
joylove Private 4 Rep 57 Posts Drives: X3 LCI Join Date: Mar 2013 Location: West Coast. iTrader: (0)	I found this post unfinished and fought I'd better update it for future visitors to the site. Seems the N52 starter is a common issue, and most people go to the battery first (understandably) when in fact the starter is (a) gonna fail later and (b) killing the batteries with the massive load (fnar) it puts on. Last edited by joylove; 01-01-2014 at 04:54 PM..
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01-01-2014, 05:27 PM	#9
ssmith96 Banned 78 Rep 1,038 Posts Drives: 07 328xi Join Date: Mar 2013 Location: Long Island, NY iTrader: (2)	My car does that when its cold it doesn't even seem like that long of a crank to be honest.
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01-01-2014, 05:34 PM	#10
joylove Private 4 Rep 57 Posts Drives: X3 LCI Join Date: Mar 2013 Location: West Coast. iTrader: (0)	The length of time and the speed of the crank are two different things though. One is the fuel pump & the anti-return valve; and the other is the starter.
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01-02-2014, 11:53 AM	#13
joylove Private 4 Rep 57 Posts Drives: X3 LCI Join Date: Mar 2013 Location: West Coast. iTrader: (0)	Mine was slow but ignorable. So I ignored it. One 100F day I get a call from the wife and it's totally dead. Luckily she could walk home and we got it towed at lunch time. Mine still needs extra time in the morning to pump the fuel pressure up. Some have added additional anti return valves. One thing it definitely isn't is slow turnover any more. It turns over like a normal car.
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