so my 2008 Cooper S was having the death rattle at startup so I ordered the new tensioner and did the install today. Went very smooth however after starting car the idle is now very rough and car seems like it wants to stall.

any ideas on what this could be or what I should check?

car had no idle issues at all before the work.

 

Chance it could be out of time.

 

I thought timing could not change with just tensioner change. As long as engine stayed static.

 

True, but you said it had death rattle. Depending on how long it went on for and how much slack was in the chain it could have jumped Time. But you said that it ran just fine up till the very second you replaced the tensioner other that rattle?

 

Correct.

 

Have you pulled valve cover and had a look at the guides, gears, chain to see if anything is noticeably wrong?

 

I have not, I will look for guide and see what I can find out

 

Keep in mind that sometimes the VANOS sprocket on the intake camshaft could be preloaded and under tension. once you pull the tensioner, the VANOS releases and pulls on the chain.

as mentioned before, check the timing. if you dont know how, let us know or search it up.

 

So I had some time to go out yesterday and look at the car again. Figured it was one of 3 things after doing a lot of research;

1) I used MAF cleaner and maybe it was still damp on the MAF causing me some issues.

2) I knocked the CAM sensor by the tensioner out of place and it was loose.

3) The chain needs to be replaced... KILL ME.... lol



So pushed the car out of garage and opened hood. Checked all lines to make sure they were secure and even checked the CAM sensor. Everything was 100%. Started the car up and it sounded awesome!!!! NO DEATH RATTLE AT ALL.. Perfect idle. Was over the moon.

Car started to warm up and all of a sudden CEL came on and car started to buck around RPM's and stalled. Noooooooooooooooooo!!!!

Well at least I now have a cel I can look up. Scanner said P1497, looked it up and there was not much except for it being generic BMW code, however on any Turbo BMW engine this code seems to always be a vac leak.

Started to look over everything. No loose clamps, all connections good, triple checked the PCV hose everything perfect... Start thinking to myself about what I have pulled off and or moved. So I disconnect the PCV hose as I recall pushing it out of the way when I was doing the tensioner. As soon as I disconnect it I can see its turning way more then it should.





There is my issue!!! THANK GOD!!!! I could not see it was broke because it had that mesh over it, I assume once car ran for a bit the valve cover opened up and since it was broke engine went to hell with vac leak.


Ordered a new one this morning, just hoping its not too hard to replace since I dont know where the other side is exactly lol



Thank you everyone for the help!

 

http://www.realoem.com/bmw/enUS/show...diagId=11_3915

You may have to remove the intake manifold. it isnt a bad task and take your time doing it. there are alot of things attacked and there is a "hidding" 10mm in the back you have to reach and unbolt before you can even move the manifold.

#6

http://www.realoem.com/bmw/enUS/show...diagId=11_3933

 

That sucks, I was really hoping I could just reach down and unhook from driver side of the engine.

 

You could try, but i know it a bit tight. try to fish it out slowly. also check NAM for posts on how to replaced it, if any. when replaced mine, i just took the manifold out and replaced it. I have already removed that bolt to rebuild the head.

 

Found a few posts, apparently its tight but you can do it by just removing the airbox.