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Old 10-03-2012, 03:59 AM
Tiko530 Tiko530 is offline
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Location: NYC
Join Date: Sep 2012
Posts: 42
Mein Auto: 2003 530i
Post Vanos Seal Replacement

I recently ordered a new set of double Vanos seals from you for my 2003 530i from Beisan Systems. Shipped very quickly and I was very eager to change the seals considering all the glowing testimonials I read from you guys.

To give you a bit of background, I purchased my car about one month ago, did not have a complete service history but assumed the seals had not been changed even though my car did NOT have any of the characteristics described as symptoms of seal failure ( rough idle, sluggishness below 3,000 RPM etc...).

Yesterday I decided to change the seals, I am by no means an expert DIY-er but since the instructions on the site were so good and I so much positive feedback I figured I would do the job myself. Took me quite a bit of time, also replaced my spark plugs and pre-cat oxygen sensors in the process.

Immediately after the replacement I noticed that my car was significantly more sluggish, it was as if the Vanos seal replacement had worked in reverse. I attributed it initially to the break in period but since then have read that it should never be worse off than prior to the replacement and since the replacement I have driven the car for close to 100 miles with no noticeable improvement.

Here are some possible issues that may have had an effect: (like i said I am a novice at mechanical work and made some mistakes in the process)

1. When I first lifted the Vanos unit out of it's spot I noticed what looked like black flat seal or o-ring of some sort, it was broken and pretty much flattened out into its lenght, half was underneath the lower part of the timing belt and the other half was sticking out when I took the Vanos out. It was flat, about 3 mm wide and seemed like hardened rubber, not much different than the teflon seals on the Vanos pistons but significantly wider. I am only giving this description because I looked in the area but could not figure out where this had come from and till now have no idea what purpose it served. I removed it.

2. During the removal of the bolts holding down the Vanos exhaust piston and spring the piston flew out under the pressure of the spring and fell about 3 feet down to a concrete floor. I inspected the piston and did not find any significant damage though.

3. One of the Vanos piston caps was slightly damaged during removal. A small section of the side wall of the piston cap (less than 1/4 of the circumference) broke off, I reinstalled as it was and it went back in its place normally.

I don't know if any of these 3 issues may have played a role but I am hoping one of you guys might have heard some sort of similar complaint in the past or had a similar issue yourselves and might have some info to help me diagnose what I might have done wrong or what issue/issues I need to address to improve the performance of the car at least back to pre-seal replacement levels.

P.S. when I say sluggishness, it doesn't feel horrible, if I hadn't driven the car before I might not have realized that something was wrong, but I really have to step hard on the gas to make the car move
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