N42 Valvetronic Vibrations.....

[beem]

Hi Guys,

I'm sure there would be some guys out there who experienced vibrations during idling (with D engaged) on their valvetronics. My car seems to vibrate frequently though there are some occasions the car is very well behaved. I believe this problem was solved with the N46 engines. Anybody can tell me what's the difference between the N42 and N46? Is it just the ECU?

Additionally, my rpm seems to dip occasionally...does this has anything to do with the knocking sensors?

Please share ur experience and any kind of solution to this never ending problem. Its been bugging me for a WHOLE FREAKING YEAR now....

There is no mods to the car except for the Volker plugs and i'm running on 10W-50 Castrol RS.


Thanks guys...any feedback will help ...

 

[BMWSILVER]

Re: N42 Valvetronic Vibrations.....

Hi

My car is also E46 318i (N42 Engine) and experienced vibrations during idling (with D engaged) too. But after several complaints to PML and they told me this is normal for our car
I gave up and now get used to it liow

During the monthly meet-up you can check out with other owner E46 318i to feel the difference

Next thing I found out of our car is the Engine Casket (I think its called the - Rocker Arm Casket).
It will leak and mine leaked liow and need to change ==> This also another common problem

Good luck

 

[bmwF1]

Re: N42 Valvetronic Vibrations.....

I am running the N42 engine and used to have all sorts of problem with the vibrations.

Heavy vibration and dip in idling can be due to a lot of things. For my case it was first because of the ignition coil and the second time it is due to mass air flow sensor. It can be due to many different issues but this is not normal at all. Get it fixed asap cause my car broke down due to the air flow sensor.

If you experience slight vibration, it is normal i guess. PML adjusted the idling rpm higher to remove the slight vibration, got a bit better after that.

 

[louis]

Re: N42 Valvetronic Vibrations.....

sounds like the ignition coils... common problem with the N42 if i recall.

although i might get flamed by some members for saying this... you can't discount the possibility of your spark plugs being the cause as well. happened to a forum member with the M54 engine some time ago, with a different brand of plugs though. do a search.

revert back to stock plugs and see if the problem goes away. if your car's still under warranty, you'll definitely want to switch back to stock before you go in to claim.

also, is the oil you're using approved by BMW?

 

[martmode8850]

Re: N42 Valvetronic Vibrations.....

think the valvetronics are on 0W-30 engine oil???

 

[SL2]

Re: N42 Valvetronic Vibrations.....

think the valvetronics are on 0W-30 engine oil???

10W-50 is the recommended viscosity for valvetronic engines. Some would have gone for 5W-40 but there's a tendency to 'lose' oil at a faster pace over time.

 

[beem]

Re: N42 Valvetronic Vibrations.....

Thanks guys...

I've tried reverting back to the ori spark plugs..doesn't help....

All 4 ignition coils have been changed..doesn't help...

Timing increased...doesn't help...

Monitored the engine cylinder compression i think..can't make out some of the figures...but seems like cylinder 4 is not in the green zone....somewhat working borderly between yellow and green....it carries a unit written as 1/s2....wonder what it is....not sure what's the cause of it as well...

As what SL2 mentioned...there's been cases of valvetronics using 5W-40 to have their oil top-up....they recommended 10W-50..

 

[ivo]

Re: N42 Valvetronic Vibrations.....

Speaking of 5W-40 oils, on the same grade, I've had to top up more than 1.5 liters across 8 months since the last oil change. Thought there was a leak or something.

My FL E46 doesnt really have the vibration problem, but it can be pretty noisy at idle... BVO said its the fan belt and some pulley stuff. Not a serious issue.

 

[BMWSILVER]

Re: N42 Valvetronic Vibrations.....

Speaking of 5W-40 oils, on the same grade, I've had to top up more than 1.5 liters across 8 months since the last oil change. Thought there was a leak or something.

My FL E46 doesnt really have the vibration problem, but it can be pretty noisy at idle... BVO said its the fan belt and some pulley stuff. Not a serious issue.

Hi ! ivo.

I think there is some leak somewhere in your engine.

As for my car never need to top-up any engine oil for the past 2.5 years.
Recently, send my car to PML for Inspection I and they told me there are some leak in the engine casket. But still I did not top-up any engine oil so far.

You should ask BVO or J4C to check again..........

 

[beem]

Re: N42 Valvetronic Vibrations.....

Come on guys....Nobody liao??

 

[SL2]

Re: N42 Valvetronic Vibrations.....

Come on guys....Nobody liao??

I might be wrong but I believe it should be down to these 2 things: Calibration and tuning. Try getting your ECU re-tuned. That should stop the vibrations. But if you do not want to overide your original ECU, drop in a piggyback and start tuning from there.

 

[yendor]

Re: N42 Valvetronic Vibrations.....

IMO, I think you problem may be just boiling down to a dirty valve train issue. What i suggest is to change your engine oil to 40 weight oil and perhaps you can try pouring in a bottle of friction modifier to help things along. Thereafter, get a bottle of Fuel injector cleaner from autobacs or anywhere else. (STP brand cost about $23 or so). Top up your tank and add in the injector cleaner. Head up to Malacca (in the dead of night) and hit at least 3500rpm - 4000rpm and drive straight up to Ayer Keroh.

The constant speed will ensure that all the carbon foul up on the valves are cleared off and that has the effect of ensuring better sealing which in turn will promote better idling.

Give it a try..... its only 3-4hrs of your time and about $100 worth of fuel and cleaner......

Anyway, this "exercise" is not just limited to valvetronic engines but also all engines. Guys that always hit the NS highway can vouch that their cars come back smoother and slightly more torquey after returning.

Cheers

 

[piggyboyz]

Re: N42 Valvetronic Vibrations.....

I dunno the extend of the vibration of the car u all are talking about, but does the car still stall after reverting back to stock plugs and changing ignition coil ?

If the car no longer stall but vibrates, then is the vibration occasional or constantly like that ? the other thing that needs to be asked is... What is the age of the car ? Is the engine mounting checked ? Are u one of those who drive around city all the time and harldly drive hard ? All these are the possibilities that the car will stall / vibrate.

To start off, the 4 cyclinder is not as refined as the 6 cyclinder and BMW, being a RWD, mounts the engine longitudinally and unlike a lot of japanese car, which mounts it tranversely since it's a FWD. The result ? more vibration cos the engine can rotate in a left right direction as opposed to the tranverse mount angine which can only rotate in a front rear direction, which the weight of car can counter it effectively and hence, almost 0 vibration.

Try sitting in a E36 318iS M44 engine and the vibration is someting u have to get used to.

Other than that, it's the car age. The engine mount wears out, especially the RHS one due to the exhaust manifold there causing heat induction to the mounting.

If u hardly drive the car hard, u realised more carbon build up in the air intake system and this again, will affect the throttle body / idling valve, which may cause vibration. Try doing this, start the engine and leave it running with the aircon on for 30-45mins. When u try to move off after that, the engine may just die..... The park goer will know this hurhurhur !!!

hope this helps...

 

[yendor]

Re: N42 Valvetronic Vibrations.....

Piggy, is seems like you've spent alot of time in a parked E36 hor???? ; )

Anyway N42 valvetronic engine got no throttle and idle valve. therefore they are more affected by any valve deposits. Therefore should try and "lut" the car every now and then..

Cheers

 

[SL2]

Re: N42 Valvetronic Vibrations.....

Anyway N42 valvetronic engine got no throttle and idle valve. therefore they are more affected by any valve deposits. Therefore should try and "lut" the car every now and then..

Cheers

Swee2x.. Gives me more reason to "lut" now!

 

[yendor]

Re: N42 Valvetronic Vibrations.....

Swee2x.. Gives me more reason to "lut" now!

Bro, ever realise why your car never have those idling problems? Ignition coils apart or broken/collapsed hoses (like in rodders case last time), the valvetronic engine will not suffer from the idling valve or throttle issues like the 6 cyl engines.

"Lut" away bro. But lke the ribena advertisement says ' Yes, but not too much'

Ha hah

 

[rodders]

Re: N42 Valvetronic Vibrations.....

Wah.......so long ago and you still remember that one.

 

[beem]

Re: N42 Valvetronic Vibrations.....

piggyboyz,
I changed my mounting recently...the problem still persists.. Changed fuel regulator as well...problem still there...However, my car doesn't stall. The vibration can be quite terrible I would say...seems like shaking the whole car during routine traffic stops..but sometimes its mild..and sometimes, none to the extent...

hmm..my car is kinda like a weekend car...i only drive it like 2 days a week...ocassionally i drive it hard..but once i drove it hard and stop...the car vibrates terribly...the rpm dips occasionally as well and that makes it worse...

Yendor,
Didn't know the N42 doesn't have throttle and idle valve. I was always under the impression there's a idle control valve that needs cleaning....is that true? Anyway, if you read my last post...the GT1 actually detected my cylinder 4 is not "cycling" (i think) within specification. I am not sure what the numbers mean but the units are specified in 1/s2 (read as one over s square). Any idea?

 

[piggyboyz]

Re: N42 Valvetronic Vibrations.....

It's normal that egine hunt a bit after driving it hard, especially for the 4cyc.

As for cyclinder 4 not firing, then it's probably the ignition coil not working or the spark plug is faulty.

It's easy to trace ur fault now.

Effectively the engine is running on only 3cyclinder since the ECU will pick up that there is a lot of unburnt fuel in that cyclinder and shut off the fueling to it.

If it's intermittent, my guess is that the ignition coil is gone. Easy way to confirm will be to swap the coil to another cyclinder and see if the GT1 register that the fault go to that particular cyclinder.

 

[beem]

Re: N42 Valvetronic Vibrations.....

The cycling of the 4th cylinder is actually marginally failing according to the GT1 readout. WIll try to swap and see. But these ignition coils are the newer BOSCH ones which they claim does not fail over the old ones...