E91 Straight Six Bearding
Discussion
It didn't fix the issue. 
Symptoms:
Unsteady/lumpy idle, usually when cold, lasting 5-10 seconds (doesn't feel happy) and then seems to settle.
When driving the car it seems ok. Kick down fine, revs all the way to the red line with good power. Once the EML came on when my wife was driving but never happened to me.
Sometimes if you blip the throttle (foot to the floor) it won't rev properly 'stuttering':
https://streamable.com/83kc7
On restarting the car, the throttle blip seems ok:
https://streamable.com/amjx1
The Vanos intake code (28A2) is back again.
No other relevant codes that I can find (also had A6CF and 9CB4)
Having read up around the fault code, I am worried it could be the camshaft bearing edge.
What do you guys reckon?
Symptoms:
Unsteady/lumpy idle, usually when cold, lasting 5-10 seconds (doesn't feel happy) and then seems to settle.
When driving the car it seems ok. Kick down fine, revs all the way to the red line with good power. Once the EML came on when my wife was driving but never happened to me.
Sometimes if you blip the throttle (foot to the floor) it won't rev properly 'stuttering':
https://streamable.com/83kc7
On restarting the car, the throttle blip seems ok:
https://streamable.com/amjx1
The Vanos intake code (28A2) is back again.
No other relevant codes that I can find (also had A6CF and 9CB4)Having read up around the fault code, I am worried it could be the camshaft bearing edge.
What do you guys reckon?
ferrisbueller said:
Worth having a look on E90 forum. Lots of threads on lumpy idling N52s with suggestions ranging from updated software on the ECU, vacuum leaks, fuel injector cleaning etc.
Had a look at those when the original fault came up. With so many potential problems, tbh I'm none the wiser!g3org3y said:
ferrisbueller said:
Worth having a look on E90 forum. Lots of threads on lumpy idling N52s with suggestions ranging from updated software on the ECU, vacuum leaks, fuel injector cleaning etc.
Had a look at those when the original fault came up. With so many potential problems, tbh I'm none the wiser!ferrisbueller said:
g3org3y said:
ferrisbueller said:
Worth having a look on E90 forum. Lots of threads on lumpy idling N52s with suggestions ranging from updated software on the ECU, vacuum leaks, fuel injector cleaning etc.
Had a look at those when the original fault came up. With so many potential problems, tbh I'm none the wiser!- Had a grumble
- Replaced Vanos intake solenoid
- Exhaust and inlet CAM sensor replaced (Dec 2017)
- Spark Plugs replaced (Dec 2017)
Oddly enough, and it may be coincidence, I think this has only really been an issue since I had the first lot of work done on the car which consisted of replacing the waterpump (and thermostat), doing the sump gasket (subframe off job) and oil filter housing gasket. I asked them to change the oil at the same time (rather than just replacing the old oil).
When the car is in Drive and you're holding it on the brake also feels like there's slightly too much vibration through the steering wheel.
I've noticed there's a bit of a cam cover gasket leak (do all N52s do this? My Z4 is the same). Could that be contributing? I wouldn't expect it to throw up a Vanos code or cause the intermittent throttle blip issue (sorry about the poor quality vids btw).
Edited by g3org3y on Sunday 4th August 22:10
g3org3y said:
Yep, earlier today. BMW OEM item. Only the intake solenoid (as that was the only DME code (2A82) that came up)
Sorry, I missed that! This may be some help, https://www.e90post.com/forums/showthread.php?p=19...
I haven’t had to fix this problem before. The N52 is a pretty reliable engine.
helix402 said:
Sorry, I missed that! This may be some help,
https://www.e90post.com/forums/showthread.php?p=19...
I haven’t had to fix this problem before. The N52 is a pretty reliable engine.
Thanks for the link, will check it out.https://www.e90post.com/forums/showthread.php?p=19...
I haven’t had to fix this problem before. The N52 is a pretty reliable engine.
As I mentioned earlier, once the idle has settled, the car behaves (to my ignorant self) fine. No drop in power, revs through with no issues.
Could something that was changed during the above remedial work have inadvertently resulted in the issue?
Yes, I heard the N52 was the engine to go for (versus the later N53). But so far my experience of it in both this E91 and my Z4 give me the impression it's a bag 'o niggly s
te compared to my old M52 or M50.bmwmike said:
g3org3y said:
ferrisbueller said:
Was that £104 for the pair?
No, each.
Not cheap especially when it appears you can get an aftermarket pair for about a quarter of the price.
TBF, once the idle has settled the car seems ok. As I said, drives fine, no loss of power.
Been looking at this: https://static.nhtsa.gov/odi/tsbs/2012/SB-10032779...
Will check the oil filter cap to make sure that the insert hasn't been inadvertently removed.
Not sure if there's merit in changing the exhaust vanos solenoid as well (tho the code 2A87 has never come up).
As I said, it's odd as I'm sure it only started to do this after the first bit of work I had done on the car which involved the waterpump, sump gasket, oil filter gasket and included an oil and filter change.
Speaking of oil, the sensor seems inconsistent. A few weeks back on a drive to Gatwick it told me it was down to minimum and needed 1L adding. I added 500ml and iirc it took it to just over the midway point. Last weekend it showed 1/4 over minimum. Yesterday it was up to 3/4. No blue smoke. No black smoke.
Could it be a PCV leak?
When I get home tonight I'll check the oil filter insert and see if there's a hiss on opening the oil cap on idle.
There are two filters in the VANOS solenoid oil galleries on the RH side of the cylinder head, towards the front. They are recessed in to the head about 20mm so are difficult to see without a mirror. Torks 30 with a aluminium head.
These can clog up restricting oil supply to the VANOS solenoids.
Is your oil of the correct viscosity? The symptoms described being more prevalent in cold running may indicate in correct oil.
These can clog up restricting oil supply to the VANOS solenoids.
Is your oil of the correct viscosity? The symptoms described being more prevalent in cold running may indicate in correct oil.
stevesingo said:
There are two filters in the VANOS solenoid oil galleries on the RH side of the cylinder head, towards the front. They are recessed in to the head about 20mm so are difficult to see without a mirror. Torks 30 with a aluminium head.
These can clog up restricting oil supply to the VANOS solenoids.
Is your oil of the correct viscosity? The symptoms described being more prevalent in cold running may indicate in correct oil.
Thanks, will check it out.These can clog up restricting oil supply to the VANOS solenoids.
Is your oil of the correct viscosity? The symptoms described being more prevalent in cold running may indicate in correct oil.
Do you think it's worth changing the exhaust solenoid as well?
5w30, so should be correct.
G3org3y,
I tried to be a dick with mine to see if I could provoke symptoms similar to yours with mine. Mine has 142,000 miles on it, original VANOS solenoids.
When blipping the throttle at a standstill it's fine, but the only time I can replicate a 'jolt' is flooring it from under 1,200 revs whilst in gear. There's a jolt of a lack of power, and then it pulls smoothly.
Unless I act harshly (flooring it quickly at very low revs) it's dead fine, but I think come the next service (150,000 miles) I will replace the solenoids, and clean out the check valves and the like in the head. From some Googling, it seems that the VANOS can't adjust the oil pressure properly in time, and the timing goes out for these sort of symptoms. Steve said about cleaning out various bits, and I would do that too. Unless it gets really bad though, I'd 'live with it' for a while, because firing the parts cannon at these sorts of issues can add up really quickly, and make no difference barking up the wrong tree.
I tried to be a dick with mine to see if I could provoke symptoms similar to yours with mine. Mine has 142,000 miles on it, original VANOS solenoids.
When blipping the throttle at a standstill it's fine, but the only time I can replicate a 'jolt' is flooring it from under 1,200 revs whilst in gear. There's a jolt of a lack of power, and then it pulls smoothly.
Unless I act harshly (flooring it quickly at very low revs) it's dead fine, but I think come the next service (150,000 miles) I will replace the solenoids, and clean out the check valves and the like in the head. From some Googling, it seems that the VANOS can't adjust the oil pressure properly in time, and the timing goes out for these sort of symptoms. Steve said about cleaning out various bits, and I would do that too. Unless it gets really bad though, I'd 'live with it' for a while, because firing the parts cannon at these sorts of issues can add up really quickly, and make no difference barking up the wrong tree.
g3org3y said:
Thanks, will check it out.
Do you think it's worth changing the exhaust solenoid as well?
5w30, so should be correct.
5w30 should be fine.Do you think it's worth changing the exhaust solenoid as well?
5w30, so should be correct.
Are you getting any codes?
INPA software has some useful features for checking VANOS function. You can set the cam angle manually through the software to various different angles. By doing this you can check the response times, and if it seems sluggish it is an indication.
You could try swapping them over In for Ex and see if there is a change to symptoms.
g3org3y said:
helix402 said:
Sorry, I missed that! This may be some help,
https://www.e90post.com/forums/showthread.php?p=19...
I haven’t had to fix this problem before. The N52 is a pretty reliable engine.
Thanks for the link, will check it out.https://www.e90post.com/forums/showthread.php?p=19...
I haven’t had to fix this problem before. The N52 is a pretty reliable engine.
As I mentioned earlier, once the idle has settled, the car behaves (to my ignorant self) fine. No drop in power, revs through with no issues.
Could something that was changed during the above remedial work have inadvertently resulted in the issue?
Yes, I heard the N52 was the engine to go for (versus the later N53). But so far my experience of it in both this E91 and my Z4 give me the impression it's a bag 'o niggly s
te compared to my old M52 or M50.What mine actually turned out to be was the large DISA valve, the butterfly vane had exploded and was sitting in my inlet valves. Engine didn't injest anything fortunately and I fished all the bits out of the intake manifold. The replacement part had been redesigned by BMW with a metal shaft, so all good now. But this caused a lumpy idle, without anything else particularly obvious and no codes initially.
JakeT said:
G3org3y,
I tried to be a dick with mine to see if I could provoke symptoms similar to yours with mine. Mine has 142,000 miles on it, original VANOS solenoids.
When blipping the throttle at a standstill it's fine, but the only time I can replicate a 'jolt' is flooring it from under 1,200 revs whilst in gear. There's a jolt of a lack of power, and then it pulls smoothly.
Unless I act harshly (flooring it quickly at very low revs) it's dead fine, but I think come the next service (150,000 miles) I will replace the solenoids, and clean out the check valves and the like in the head. From some Googling, it seems that the VANOS can't adjust the oil pressure properly in time, and the timing goes out for these sort of symptoms. Steve said about cleaning out various bits, and I would do that too. Unless it gets really bad though, I'd 'live with it' for a while, because firing the parts cannon at these sorts of issues can add up really quickly, and make no difference barking up the wrong tree.
It's definitely an odd situation.I tried to be a dick with mine to see if I could provoke symptoms similar to yours with mine. Mine has 142,000 miles on it, original VANOS solenoids.
When blipping the throttle at a standstill it's fine, but the only time I can replicate a 'jolt' is flooring it from under 1,200 revs whilst in gear. There's a jolt of a lack of power, and then it pulls smoothly.
Unless I act harshly (flooring it quickly at very low revs) it's dead fine, but I think come the next service (150,000 miles) I will replace the solenoids, and clean out the check valves and the like in the head. From some Googling, it seems that the VANOS can't adjust the oil pressure properly in time, and the timing goes out for these sort of symptoms. Steve said about cleaning out various bits, and I would do that too. Unless it gets really bad though, I'd 'live with it' for a while, because firing the parts cannon at these sorts of issues can add up really quickly, and make no difference barking up the wrong tree.
The only provocable sign is the throttle blip and that will go back to normal once the car is switched off and then back on. Otherwise it's the unsteady idle for a short period on start up.
My concern is a situation where the car starts to be unreliable and not start. I bought this car as wife is expecting end of Sept. Last thing I want is for it not to start on the day she goes into labour!
stevesingo said:
5w30 should be fine.
Are you getting any codes?
INPA software has some useful features for checking VANOS function. You can set the cam angle manually through the software to various different angles. By doing this you can check the response times, and if it seems sluggish it is an indication.
You could try swapping them over In for Ex and see if there is a change to symptoms.
The only code is the 2A82 Vanos Inlet. I don't mind replacing the Vanos exhaust solenoid as well but that code doesn't seem to come up. I'll check out those filters as well.Are you getting any codes?
INPA software has some useful features for checking VANOS function. You can set the cam angle manually through the software to various different angles. By doing this you can check the response times, and if it seems sluggish it is an indication.
You could try swapping them over In for Ex and see if there is a change to symptoms.
As mentioned, the odd thing about it is that I'm sure it started after the original round of work was done.
zippyonline said:
I had a lumpy idle on my N52 a while back. After the simpler things, the more complex ones it could have been and I did (coz I had to change the valve cover gasket anyway, so this was 5 minutes extra work to change, but admittedly a pricey sensor - but apparently they do go wrong and get oil contaminated.) That's the e shaft sensor which is in the valve cover, at the front. https://www.e90post.com/forums/showthread.php?t=69...
What mine actually turned out to be was the large DISA valve, the butterfly vane had exploded and was sitting in my inlet valves. Engine didn't injest anything fortunately and I fished all the bits out of the intake manifold. The replacement part had been redesigned by BMW with a metal shaft, so all good now. But this caused a lumpy idle, without anything else particularly obvious and no codes initially.
Thanks for the info. It now seems to have a valve cover gasket leak, so perhaps an opportunity to get that looked as as well.What mine actually turned out to be was the large DISA valve, the butterfly vane had exploded and was sitting in my inlet valves. Engine didn't injest anything fortunately and I fished all the bits out of the intake manifold. The replacement part had been redesigned by BMW with a metal shaft, so all good now. But this caused a lumpy idle, without anything else particularly obvious and no codes initially.
Was your lumpy idle all the time?
g3org3y said:
Thanks for the info. It now seems to have a valve cover gasket leak, so perhaps an opportunity to get that looked as as well.
Was your lumpy idle all the time?
I would say intermittent, and more like the odd grumble/hiccup/stutter. People who don't know about cars told me I was imagining it, but I very much wasn't and was very glad that I had kept looking when I found out what it was!Was your lumpy idle all the time?
g3org3y said:
Oddly enough, and it may be coincidence, I think this has only really been an issue since I had the first lot of work done on the car which consisted of replacing the waterpump (and thermostat), doing the sump gasket (subframe off job) and oil filter housing gasket. I asked them to change the oil at the same time (rather than just replacing the old oil).
Just a thought, your thought process might not be that far off. Vanos etc runs on oil pressure, so if there any any niggles in that respect, they will show on cold start first. Now, everyone knows about the bearing ledges and their scoring issues leading to a slight lack of pressure (not ideal if your code is inlet side as thats part of the head on the N52), but another thing that is often overlooked is the oil filter cap insert - show below as the green ring:
If that is removed/not replaced/damaged as part of an oil change, the system wont hold pressure when first started.
In addition, damage to the internet filter of the oil cap can lead to further vanos related issues as details here in SI B11 02 08: https://static.nhtsa.gov/odi/tsbs/2012/SB-10032779...
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