[TheSnowKeeper]

Hi everyone! Has anyone had any experience changing or removing and cleaning their VANOS solenoids?

I am having a rough idle, nothing serious, but I'm paranoid and I want to fix it. So I'm replacing plugs, coils, and cleaning the VANOS solenoids, which were commonly found solutions to a rough idle on the M235i.

It's really tight to get at them because of these pipes leading to my oil filter. Does anyone have any resources or experience doing this? I'm hesitant to start taking things off without any sort of guide, and none of the youtube videos have these pipes in the way. I also tried to use this thread to find literature, even paying for an account, but I can't find anything for my car:
https://www.2addicts.com/forums/show....php?t=1555170

Picture for reference,

Thanks in advance!!

[Pray for Mojo]

Our cars have an additional oil cooler, that's what those lines are for.

Have you ran a tank or two of Techron to see if it would clean up the idle.

[TheSnowKeeper]

Originally Posted by Pray for Mojo

Our cars have an additional oil cooler, that's what those lines are for.

Have you ran a tank or two of Techron to see if it would clean up the idle.

Oh, I see. How difficult would it be to move those lines for the oil cooler during the change?

I did run one tank of Techron through, and I didn't really notice a difference. I also checked the OBD2 for codes, but there weren't any errors listed. I feel like it can't be something big, but I don't want to let it get worse.

Thank you for replying so quickly!

[XutvJet]

Do you have any engine modifications? Stock intake and air filter?

[TheSnowKeeper]

Originally Posted by XutvJet

Do you have any engine modifications? Stock intake and air filter?

Nope! Everything is stock!

[XutvJet]

Sure your charge pipe isn't leaking?

Can you better describe the idle issues you're having?

I've been on this forum for 5 years now as well as the F30 series forums and I can't recall anyone cleaning the VANOS solenoids. I know this was an issue with the N54s and cleaning is considered routine maintenance, but the N55 uses ungraded VANOS solenoids to reduce the potential for gunking up.

[TheSnowKeeper]

Originally Posted by XutvJet

Sure your charge pipe isn't leaking?

Can you better describe the idle issues you're having?

I've been on this forum for 5 years now as well as the F30 series forums and I can't recall anyone cleaning the VANOS solenoids. I know this was an issue with the N54s and cleaning is considered routine maintenance, but the N55 uses ungraded VANOS solenoids to reduce the potential for gunking up.

Yeah, so basically it's been shaking a bit side to side, which I can feel when I'm sitting still. You can feel it in the pedals and in the shifter. It's much worse when cold, but it doesn't go away when hot. At speed you don't really notice it. I also feel like it's not as responsive as it used to be on acceleration.

This is my first BMW, so I'm new to VANOS altogether. I wasn't aware this issue is kindof obsolete, because I'm pretty sure I found that solution in a video about a 3-series from a few years ago. This weekend I did a spark plug and coil change, and that seems to have helped quite a bit (maybe it's half as bad as it used to be).

Once I asked the dealer about it when I was in for an oil change and they kindof shrugged.

I will definitely look into the charge pipe! I didn't come across that much before, but now that I'm using the correct search term I'm seeing it come up a lot. Are there any other culprits I can check on while I'm ordering parts/crawling around?

Thank you for your reply!

[MLJR235]

Have you checked out your engine mounts? You may have one that's damaged and no longer dampens the engine vibrations. This engine moves quite a bit at idle and you feeling it at the interior level leads me to believe one of the dampeners is not doing its job.

To thoroughly inspect them both, you will have to raise the front end and remove the plastic cover. Once removed, you will have easy access to them.

[TheSnowKeeper]

Originally Posted by MLJR235

Have you checked out your engine mounts? You may have one that's damaged and no longer dampens the engine vibrations. This engine moves quite a bit at idle and you feeling it at the interior level leads me to believe one of the dampeners is not doing its job.

To thoroughly inspect them both, you will have to raise the front end and remove the plastic cover. Once removed, you will have easy access to them.

That's a great tip. I hadn't even thought of that being a problem, so I will do some poking around. Thanks!

[XutvJet]

Originally Posted by TheSnowKeeper

Are there any other culprits I can check on while I'm ordering parts/crawling around?

- Make sure to use OEM Bosch plugs (stock gap too) and coil packs. Other makes can have issues. OEM is key for these particular parts.

- Check around the charge pipe at the throttle union and look for cracks. You can remove the charge pipe c-clip and pull it off the throttle body to better inspect. The stock charge pipe will not leak/crack at the intercooler union.

- Remove and clean the MAF sensor with electronics cleaner. It's the sensor mounted in the intake pipe just forward of the airbox.

- Make sure you're running a paper filter and not an oiled one.

- Inspect your engine mounts. I believe it's the one on the passenger side that tends to die an earlier death. You'll need to get under the car and remove the large lower cover to inspect this.

- Inspect transmission mounts. These are easily replaceable too and cheap. I installed slightly stiffer M2/3/4 mounts.

- Run quality fuel, not off brand stuff. Run 92-93 octane if you can find it.

[TheSnowKeeper]

Originally Posted by XutvJet

- Make sure to use OEM Bosch plugs (stock gap too) and coil packs. Other makes can have issues. OEM is key for these particular parts.

- Check around the charge pipe at the throttle union and look for cracks. You can remove the charge pipe c-clip and pull it off the throttle body to better inspect. The stock charge pipe will not leak/crack at the intercooler union.

- Remove and clean the MAF sensor with electronics cleaner. It's the sensor mounted in the intake pipe just forward of the airbox.

- Make sure you're running a paper filter and not an oiled one.

- Inspect your engine mounts. I believe it's the one on the passenger side that tends to die an earlier death. You'll need to get under the car and remove the large lower cover to inspect this.

- Inspect transmission mounts. These are easily replaceable too and cheap. I installed slightly stiffer M2/3/4 mounts.

- Run quality fuel, not off brand stuff. Run 92-93 octane if you can find it.

Thank you, friend! This is a great list! I'm on it.