udfxrookie

So all this started with some valve seals that needed replaced.... I replaced, timed without the chain tensioner tool (as for some reason it didn't come in my kit)and got my first error code. Took everything apart and re timed WITH the chain tensioner tool and the exhaust seems to be slipping CONSTANTLY.... If I'm doing something stupid PLEASE let me know so I can get this guy fixed and running again.

So here is the initial timing which looks gold:

Proof of good timing (2 full revolutions of engine):

1st start (no fuel in fuel rail)

End result = BAD TIMING SOMEHOW

udfxrookie

Got a few people saying Vanos system... As in cam sensors tell Vanos to adjust cam gears and as intake is in sync something on exhaust side is wrong. I'm going to try setting the timing again and swapping exhaust and intakes cam sensors to see if the problem follows. (Along with ensuring a solid battery)

This is based on being able to rotate 4 full revolutions (barcode on top, turning until barcode back on top x 4) and timing still being proper, timing only gets messed up when I start the car and the "vanos" system kicks in... And is very apparently adjusting

Anyone with similar experiences, tips on timing that I may not be doing, or anything you see I'm not doing properly?

seanjordan20

I would say it's the vanos system also because it's only off by a little. I would reset adaptions before starting the car to see if it makes a difference. It's memory is probably causing it to set to where it was before the new timing chain. When I do a timing chain in a BMW I always reset adaptions before starting and have never had an issue. I've only done it twice and know it's not part of the procedure but I just figure it can't hurt

udfxrookie

I also tend to reset all adaptations when doing a job like this, so that is something that was done and didn't help.... I did notice one of the Vanos filters were clogged.... crap all over it. I used a shop vac with a small hose and sucked the port it went in as well as cleaned it.... I am using an endoscope tomorrow to ensure the flywheel is set properly for TDC as several people have told me it must be off a hair (which I doubt, TDC seemed the easiest part of this job). I am also going to swap Vanos solenoids
and cam sensors just to see if the problem moves from exhaust to intake... if that fails I will have a leak down kit here Mon/Tue and will check each cylinder at TDC to see if valves are all closing properly or if one is bent somewhere...

(I will reply back once fixed as well in case someone else runs into this)

udfxrookie

So I used the endoscope to ensure TDC on crank, re set the timing, replaced exhaust vanos, reset all adaptations.... this resulted in the 2A7A so for giggles I swapped the camshaft position sensors... the result is identical.... still have a 2A7A and in infamous 3100

udfxrookie

Swapped out exhaust vanos with a new oem and it started great.... no codes... took it for a drive to the gas station 2 miles away and I get:
2A87 Exhaust VANOS, mechanism
3100

clear codes, start to leave gas station and get:
2A7A Camshaft position controller, exhaust, cold start
3100

WTF... sounds like a ticking too not the normal fuel injector sound

seanjordan20

Did you replace the solenoid or sprocket?

seanjordan20

Got the update. I was about to say that is odd that you were still having the issue. So in the end the Vanos was bad

udfxrookie

Missed the last update =(
BOTH cam gears are new by the way...
But changing the VANOS for the exhaust DID make it run great in Park/Idle.... driving it 2 miles she threw the codes again... still lost
I am going to do the leak down tomorrow and check all the cylinders

seanjordan20

Now I'm scratching my head? You changed the sprockets and still getting the code. Did you also install new bolts? That would be my next step also since the change didn't completely fix the issue especially since you changed them before an issue arose. Now if the chain or a guide broke this would make sense.