Reply to Thread

Post a reply to the thread: Vanos seals solution

Your Message

Click here to log in

Please correctly re-type the phrase f o o t d o c t o r in the form box. Re-type it without the extra spaces and put the one space where it should be. We apologize for having to do this but this silliness helps slow the spammers.


Additional Options


Topic Review (Newest First)

  • 12-21-2012, 07:46 AM
    I have this cold idle problems with 8cyl M62B44TU which is single vanos. Have you any experience with this? Gregor, Croatia
  • 03-11-2011, 05:16 PM

    Las instrucciones completas están el la página web de Rajaie. Si no entiendes inglés, usa el traductor de Google. Cualquier problema o pregunta que tengas, házmelo saber.
  • 03-07-2011, 12:20 AM

    Re: Vanos seals solution

    325i Sedan 278,000 miles, auto

    My car has high mileage as you can see. Recently it has developed a ticking sound from the timing chest which sounds like the timing chain is slapping the inside of the chest. IT only occurs from cold start up (Califoria coast so not too brutal!) More recently, it has hiccupped at low rpm or when coming to a stop. This is very similar to the symptoms I had when my Inlet cam position sensor went out.

    My mechanic checked the timing chains and said they were in excellent shape and not at all lose. In your opinion, are any of these symptoms caused by the Vanos?
  • 03-06-2011, 09:42 AM
    luis ortiz

    Re: Vanos seals solution

    me podrian enviar diagrama de como reparar vanos de bmw e46 325i 2001. quien pueda ayudarme le estare eternamente agrdecido.muchas gracias y que DIOS los vendiga...
  • 12-22-2007, 05:35 PM

    Re: Meant to add this was done by a real pro...

    I buying one. My '00 328i has symptoms at outside temps anything less than 45F.

    6 hour DIY with no special tools required? under $150 total parts bill? If you can change your own brakes, this sounds like a no-brainer.

    Thanks for your hard work! I wish BMW engineers were as dedicated to these cars. I'm looking forward to having my car be able to idle in the mornings at stoplights again!
  • 12-04-2007, 03:52 PM

    Re: Vanos seals solution

    You’re right. The old vanos units have a thin film that’s likely a sealant. This can be seen at some locations on the outer perimeter of the cover gaskets.
    I have purchase several new (rebuilt) vanos units, and none of them have any sealant. It’s a bare metal gasket against a bare vanos body.

    As you note, the vanos oil flow is controlled via PWM (pulse width modulation). The DME refreshes the oil in the oil chambers at a modulation of 100-220 Hz. Thus any slight leak will have little if any effect.

    Astute observations on your part.
    528i 5sp 06/00
  • 12-03-2007, 03:36 PM

    Re: Vanos seals solution

    I am not an expert, but here's what I say: the gaskets are not just metal, they are metal covered with rubber (silicone, vuiton, call it whatever). I did take mine apart (I have a spare VANOS in the garage) and you can see the rubber being squeezed where there was contact. However, I do not believe the leak is significant, because I think that the VANOS adjusting is a continuous process, and even a small leak will not cause any noticeable change in the angle... I was just curious if you used new gaskets, or used any sealant.
  • 12-03-2007, 02:01 PM

    Re: Vanos seals solution

    Good question.
    The vanos cover gaskets are not available separately. I did not invest the effort to reverse engineer and produce them.
    They are metal with no coating. Thus I expect they are more durable and can be reused. It seems impossible to gauge if the gaskets are leaking. I asked some seals experts about this issue, but received no definitive assessment. I'd be interested to hear a more expert opinion.

    Repair results have been quite good. My take is the gaskets are fine.
    I'm open to other perspectives.
    528i 5sp 06/00
  • 12-03-2007, 12:08 PM

    Re: Vanos seals solution

    Rajaie, did you replace the gaskets for the vanos cylinder housings? Are these available somewhere?
  • 12-01-2007, 02:41 PM

    It helps a lot, so much appreciated! I'll try your

    test next time I'm out and see what the evaluation produces.
    Please stay in business for our future!
  • 12-01-2007, 01:43 PM

    Re: Wow, you've crafted the best DIY write-up

    Thanks for the very kind remarks regarding this effort. I do really appreciate that.

    You might consider getting a copy if the BMW TIS software repair manual. The Bentley is mostly a mimic of the TIS. There are nice additions and pictures to the Bentley, but the Bentley also manages to screw up the TIS directions in some cases. I mostly like the layout of the TIS and reference it by default.
    You can acquire the TIS on ebay. The latest versions come on DVD. The BMW ETK, software parts manual, and other software documents are also quite helpful.

    The major aggravating symptom from the failing vanos is the cold weather cold start idle jolts and possible stall. This is only found on the M52TU engine (99-00). BMW became aware of the problem and patched up the next version engines, M54 & M56, software to address the symptom. M52TU owners usually indicate the symptom returns after two years from replacing the vanos.
    I bought my car, 528i 06/00, in the summer of 2003 with 51k miles. At the first sign of cold weather I started experiencing the cold ideal symptom. In early 2005 I bought a new vanos. I replaced the pistons from my old vanos with the pistons from the new vanos and reinstalling the old vanos. My idle problems resolved. I also gained some wonderful performance improvements. I used to say my car now drives like its on steroids. I noted that I lost these performance improvements in ~6 months. In two years, ~20k miles, I started experiencing the cold engine symptoms again. I removed the seals and inspected them. The O-rings had significantly deteriorated. During my development and testing process I purchased several new BMW vanos units. I installed one of them for testing, but didn’t get to removing it for 3 months, ~3k miles. Upon removal I was disgusted to see the seal fit had notably degraded. I removed the seals and found the O-rings had already suffered notable compression set.
    The Buna O-rings simply are not appropriate for the engine environment. They are not compatible with engine synthetic oil or engine temperatures.
    All the vanos units in all the engine years have these Buna O-rings. All the newly sold vanos units have the Buna O-rings. I bought a new vanos unit a year back and tested the O-rings material makeup and the result was Buna.

    One of my Beta installers had a 2003 330xi 77k miles. In his case I actually did the install my self since I wanted to take pictures and document the E46 specifics. The owner complained of hesitations at lower RPMs and a lack of passing power on the highway in 5th and 6th gear. He simply thought that’s the way the car drove. I drove his car and noted the hesitations and the lack of low end torque and power. Once I removed and opened his vanos, I noted the piston (seals) were very loose in the cylinder. I could simply insert the piston in the cylinder and let it go and have it drop without resistance to the cylinder bottom and clunk. It doesn’t get much worse than this. Once I removed the seals I noted the O-rings had completely plasticized and turned into plastic. They had flat top and bottom surfaces and had shrunk.
    Once I completed the repair and took the car for a drive, with the owner, we noted improvements in the lower end torque. We also noted the lack of hesitations. After driving for a period and breaking in the seals, he has indicated significant improvements in torque and power, and that his car drives like “a different animal”. Here is his post on the vanos forum. Remove the space. http://www.bimmer

    M54 & M56 (01+) engine owners do not experience the cold idle symptoms. They are also often not aware of their power losses. But after repairing the vanos they are quite please with the performance enhancements.
    In time, enough M54 & M56 owners will perform the repair and indicate their results that the remaining owners will become more convinced.

    Here’s a method for attempting to gage the vanos failure degradation. Get the car in third gear at ~1500 RPM on an incline. Fully depress the throttle. With a failing vanos unit the car will bog and clime very slowly. With a well functioning vanos, the car will have good torque and acceleration.

    ALL the vanos units are failing. The O-rings simply do not handle the engine environment. There can be grades of failure. This will depend on time of use and spirited driving. Sports driving will cause the engine oil temperature to peak and will intern cause increased damage to the O-rings.
    In my experience from inspecting many O-rings and speaking with many owners who have performed the repair, ALL the vanos O-rings are badly damaged.

    Hope this helps.
    Thanks again from the very kind remarks.
    I’ll be happy to try and answer further questions.
    528i 5sp 06/00
  • 12-01-2007, 12:17 PM

    Rajaje, you are hard core, excellent!

  • 12-01-2007, 08:47 AM

    Less than 35 degree F....THERE.

  • 12-01-2007, 08:46 AM

    Also, should be

    My math skills are dwindling with age.
  • 12-01-2007, 08:41 AM

    Meant to add this was done by a real pro...

    I would buy one of his kits if I were tp do this, and he probably has the thing underpriced.
  • 12-01-2007, 08:38 AM

    The problem only shows up >35 degrees F, and.....

    only if you stop and idle within the first several minutes. As soon as the engine warms a bit it disappears. The engine does not stall, but slows and surges.

    Would like to eliminate this irritant, but this is a huge amount of work for a car that will be replaced by a 335 coupe
  • 12-01-2007, 12:12 AM

    Wow, you've crafted the best DIY write-up

    for any repair I've ever seen done for the e46, and your photographs are meticulously detailed and instructive. To say nothing of the skill you've applied to understanding and solving a problem seemingly endemic to our M54 engine. Thanks for all you've done and explained.
    I'd seriously like to nominate you to redo the next Bentley.
    With 48K miles on my car, I've never experienced this dilemma, and yet you reference failures of vanos units after only 20K miles. Do you have any idea why some cars experience this failure repeatedly and why I've never seem this problem reported on this board in my four years of reading it?
    Also, is it possible that BMW has modified their parts so that perhaps my '04 engine will not suffer this malady? Or do you believe that the vulnerable vanos was used up till the end of production?
    Of course I hope that this doesn't happen to me, but will surely be a customer of yours if I get this ailment.

  • 11-30-2007, 11:15 PM

    Vanos seals solution

    As many of you know E46 6-cylinder cars are experiencing a vanos problem. A friend and I diagnosed this problem three years back. Here’s the link where we made our findings public.

    The double vanos in question is part # 11-36-1-440-142, and is found on 6-cyl engines M52TU, M54, M56. These engines are all found on E46 models. If you have an E46 6-cylinder (non-diesel, non-M3) then you have one of these engines and implicitly this vanos.
    On M52TU cars, 99-00, the failing vanos is manifesting cold weather cold engine start idle jolts and possible stall. I expect most 99-00 owners have experienced this symptom. On cold mornings the DME utilizes the vanos to help warm up the cats to bring them to operating temperature faster. When the vanos malfunctions the DME reacts badly and causes the idle jolts and possible stall. This scenario was addressed in the subsequent engines M54 and M56 with a software patch to address the DME reaction to the failing vanos. There is also apparently an update to the M52TU software that also addresses the symptom.
    The failing vanos will reduce torque and power, particularly in the lower RPM range (< 3K). Hiccups and hesitations are also experienced in the lower RPM range (< 3k). Owners are now also beginning to encounter fault codes caused by the failing vanos. These codes are all related to the vanos exhaust side.
    P1520 (BMW 104, 0x68): B (exhaust) Camshaft Position Actuator (faulty reference value).
    P1523 (BMW 106, 0x6A): B (exhaust) Camshaft Position Actuator Tight or Jammed (mechanically stuck).
    P1397 (BMW 18, 0x12): Camshaft Position Sensor B (exhaust) Circuit.
    The Camshaft Position Sensor (CPS) is a common failure. But if replacing the exhaust CPS (w/ OEM CPS) doesn’t work then it’s likely the vanos failure.

    The vanos failure is due to deteriorating vanos piston seals. The seals are a combination of outer Teflon seal ring and underneath supporting O-ring. The O-rings are hardening, shrinking, and having flat top and bottom surfaces. This causes them to lose their supporting function to the Teflon seals. This causes the piston seal function to fail and in turn the vanos function to fail.
    The OEM O-rings were tested for material makeup and were found to be made from Buna-N (Nitrile, NBR). This material is not compatible with the engine synthetic oil and high temperature. The high temperature in particular is causing its failure.

    BMW was engaged for some period regarding this matter but has indicated they have no intention of addressing the issue.

    The O-rings can be replaced with a better material to withstand the synthetic oil and high temperatures, but to replace the underneath O-rings the outer Teflon seals need to be removed and necessarily damaged. Thus the Teflon seals also need to be replaced in the process. The Teflon seals are significantly more expensive than the O-rings and need to be semi-custom manufactured. This has to be done in large volumes (thousands) to even approach a reasonable cost.
    I have taken the initiative in the past two years to pursue this endeavor and have succeeded in reverse engineering the seals and producing a seals repair kit that addresses the vanos failure. Here is the post where I recently introduced this solution.

    Here is the website for the company I created to vend the product:
    You will find more information there, including a repair procedure:
    The procedure currently addresses the E46 with the electric fan. I hope to update it soon to show the E46 mechanical fan. For now the E39 mechanical fan removal can be referenced.

    The vanos seals repair kit currently costs $60, plus $5 US shipping. It addresses all the known vanos failure symptoms. Owners have also been quite please with the performance enhancements attained from the repair.
    A new (rebuilt) vanos will solve the vanos failure, but a new vanos costs ~$500. Even more problematic, a new vanos still comes with the same failing Buna O-rings. Numerous owners have installed new vanos units only to have them fail again. I inspected my new vanos seals after 20k miles and found them to be significantly degraded.

    I will be happy to answer any questions. Please take the time to read the information in the referenced links.
    In the future, please direct your questions to the vanos forum referenced by the Beisan website.
    528i 5sp 06/00

Posting Permissions

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
1e2 Forum