vanos help!

[calletson]

Hi,

Am wondering if anyone can offer any opinions on my problem...

For the last 3 months i have had very decreased torque under 3k revs, after 3-3.5k rpm it pulls fine. I have tried to fix this issue myself and have done the following:

reconditioned vanos unit with seals and actuators.

New valve cover gasket and cvv valve.

New intake and exhaust cam sensors.

Still the problem persists, very occasionally the car will run fine low down but there is no pattern to this, 9 times out of 10 is struggles to pull from low revs.

So i have taken it to an independent and the autologic shows no signal from lambda bank 2 sensor 2, and mechanical fault code with the vanos.

The mechanic wants to remove the vanos and check the timing. Does this sound logical - if the vanos timing was out would it be ok to drive sometimes and not others?? Dont really want it stripping down again after i have just done it! Labour costs etc.

It had an oil change in January but by a run of the mill garage, Could they have put wrong oil grade in and would this theoretically cause this issue??

Or could the post cat lambda be the cause of all these issues?

The car is running rich also as carbon deposits on plugs and on the back bumper, presume because the vanos isnt working low down.

What would peoples advice be for me?

Spent so much on the car in the last 3 months Im really gettin stressed now.

Any help appreciated!

Its a 2004 3.0i by the way!

 

[Blue]

Where abouts are you mate? If anywhere near the North East then I've heard that Mr Vanos is worth a look, although he does travel nationally but I bet that costs a bit extra!!

Sounds to me like the reconditioned Vanos is still not working correctly!

 

[EdButler]

Make sure there are no exhaust manifold leaks - make sure bolts are at correct torque. Does the car make a ticking when cold at all? Leaking exhausts cause the O2 sensor to detect oxygen, hence over-richening mixture.

Curious as to why that lambda isnt showing up. However it *shouldnt* be an issue as such, as sensor 2 should be post-cat and not involved with mixture control. I could be wrong however.

Grade of oil shouldnt have any real noticable effect.

It may be worth posting on other BMW forums also (E46 fanatics, Bimmerforums) as there arent a huge amount of techies on here im afraid. Please let us know how you get on.

 

[calletson]

Thanks for the replies,

I left the car with the garage all day yesterday but they didnt do anything with it, i think they are reluctant to take it on as there is no specific fault code for an easy to replace senor etc...

What i did do yesterday is unplug the battery for an hour in a bid to reset the DME adaption values. Now when i drive the car under 3.5k revs the acceleration is hesitant and jerky and idle is now erratic, i have read that senors can be on their way out but not give a code unless they are a hard fail etc, so could this be the case? A dodgy cam sensor not bad enought to throw a code but bad enough to cause the DME to adapt for it and reduce the power. And now when i reset the adaption its taking the raw readings from a faulty sensor and being hesitant etc??

I am not a mechanic so am trying to piece together info from various internet information to solve this, so any help would be appreciated!

I tried registering on e46 fanatic but its not come back with and email yet to allow me to verify etc.

Chris

 

[calletson]

The hesitant and jerky acceleration were due to a misfire on cylinder 3, i swapped the coil pack with cylinder 2 and dried the wet spark plug in cylinder 3 and this stopped the misfiring. Still the vanos issue however. Drove the car over the weekend and no misfires, however today it has started misfiring on cylinder 3 again, so it cant be the coil pack, maybe a timing issue??

I really dont know, cant get the car into the garage untill a week on wednesday so have to drive it in the mean time for work.

Anyone any further ideas of why this could be happening? Would a vanos issue cause a misfire?

Any info appreciated!