Loss of power under load...

[OFLx5]

Question: where is this vanos solenoid?

[OFLx5]

Nobody knows what these guys are talking about?

Also, can a bad o2 sensor affect performance that bad?

[upallnight]

Originally Posted by OFLx5

Nobody knows what these guys are talking about?

Also, can a bad o2 sensor affect performance that bad?

Most of the long time posters on this forum know what it is and where it is located.



The silver thingy with the wrench on it is the vanos solenoid.

Depending if it a precat or post cat 02 sensor. Post cat sensors don't affect the engine mixture. Precat changes the fuel trim which can have an effect on the engine's mixture.

Plenty of discussions about this on this forum as long as you are willing to use the search feature instead of just posting the same old questions.

[bcredliner]

Originally Posted by OFLx5

So dealer diagnosis is: bank 2 pre cat o2 sensor, vanos solenoid... they also said to replace spark plugs but they are new ngk's, and coils as well. Not sure how good their diagnosis is.. regarding the plugs...dont even think they removed them.

The first step the BMW tech would do is check for OBC error codes and from there likely do some other troubleshooting to verify the codes were not a symptom rather than the cause. The might also look at realtime information while the engine is running. It could have a vanos code and misfires info on different cylinders traced back to plugs. Usually that is enough info to know what needs to be done but the information can be interpreted incorrectly.

[OFLx5]

UPDATE! Changed O2 sensor, no difference in performance. Car died half way home.. ended up being the fuel pump. So now I got a new fuel pump and O2 sensor in and it still doesn't pull. Only difference is decreased fuel consumption from.. 22l/100km to 17l/100km, probably from the O2 sensor.

Only stored code is 68 DME, vanos exhaust camshaft, end position not reached. There is no CEL, vanos has seals done.

What else can it be?.. timing is off? ANY help is greatly appreciated!

[80stech]

Check out that valve spool that is in the bottom right hand corner of upallnights picture, it might be sticky in it's bore especially at the bottom where it's hard to clean.

[OFLx5]

Originally Posted by 80stech

Check out that valve spool that is in the bottom right hand corner of upallnights picture, it might be sticky in it's bore especially at the bottom where it's hard to clean.

Will do tommorrow!

[upallnight]

Originally Posted by OFLx5

UPDATE! Changed O2 sensor, no difference in performance. Car died half way home.. ended up being the fuel pump. So now I got a new fuel pump and O2 sensor in and it still doesn't pull. Only difference is decreased fuel consumption from.. 22l/100km to 17l/100km, probably from the O2 sensor.

Only stored code is 68 DME, vanos exhaust camshaft, end position not reached. There is no CEL, vanos has seals done.

What else can it be?.. timing is off? ANY help is greatly appreciated!

Did you just purchase the X or did this problem suddenly appeared?

Check the compression in all the cylinders. If the disa valve was broken the pin that holds the flap in place could have gotten suckered into a cylinder and wreck havoc with the valves.

[OFLx5]

Originally Posted by upallnight

Did you just purchase the X or did this problem suddenly appeared?

Check the disa valve. The flap could be stuck or broken. If you. don't know what or where the disa valve is located better to take it in and have a tech look at it.

Recently purchased, on the way home it started having problems. Disa valve was one of the first things checked, the flap was broken and replaced with a brand new one.

[OFLx5]

Originally Posted by upallnight

Did you just purchase the X or did this problem suddenly appeared?

Check the compression in all the cylinders. If the disa valve was broken the pin that holds the flap in place could have gotten suckered into a cylinder and wreck havoc with the valves.

Pin was not loose, and the flap was intact but loose from the shaft that moves it.