Help with 2002 4.6is rough running

[bcredliner]

Disconnect one 02 sensor at a time on bank 2 when engine is running or you can disconnect one and start the engine, either way. If an O2 sensor is bad there should be little to no change in the idle. At no point are they both disconnected. Yes, the focus should be on bank 2. If the process throws and error it can be cleared.

If timing is out on bank 2 the engine would not smooth out at higher rpms but per Upallnight checking the compression would narrrow down the possibilities as to what is causing the problem if it is a something that is prior to the O2 sensors other than the cat, which could be the culprit. You can come from the engine back through the O2 sensors or from the O2 sensors back through the engine as far as a trouble shooting direction. Either way it is applying the process of elimination. Do you have what you need to check compression?

[murf]

Hi Guys,
Great feedback, thank you for that.
To answer a few questions without the quotew:
I have INPA GT1 software on my laptop and can monitor the engine realtime.
Compression check on bank 2 and all cylinders within a couple psi of 210.
New plugs.
swapped coils from bank 1 to bank 2 and no change.
I have a new post cat o2 sensor and going to put that in a couple minutes.
I agree the high voltage reading post cat on bank 2 is suspect, it should be about 4.5v if the cat is doing it's job and the adaptation is in play. I believe a high voltage reading would be a rich condition. If there was unburnt fuel it would show lean I think. The adaptaion is off the charts for bank 2. Anyone know what a positive value for adaptation means? is it trying to richen it up or lean it out?

[J.Belknap]

So you have compression and spark. All that's left is fuel, air, and timing. What happens when you swap cam sensors?

[murf]

Cam sensors check ok. here are some screen shots to ponder. I don't get the 134 error until I run for a bit and then restart. even it there was a problem with the throttle actuator it would not isolate bank 2. I did swap throttle acutators with another car. not the pedal acutator.

keep thinking guys, this is good. I have paid a sibscription to a bmw expert websight and right now I think you guys might figure it out before they do.

[murf]

As much as I hate to take the cam covers off AGAIN, I think I should concentrate on the cam timing being out of range. see the charts on page one.
Does anyone know what turning the cam pickup wheel CW or CCW results in postive or negative numbers? I would like to get these numbers close to zero I think.

[upallnight]

You need to buy or rent the special tool in order to get the CAM timing correct for the Vanos system. You just can't eyeball it. If you didn't use the special tool to set the timing when you replaced the timing guides that is your problem right there.

[murf]

Originally Posted by upallnight

You need to buy or rent the special tool in order to get the CAM timing correct for the Vanos system. You just can't eyeball it. If you didn't use the special tool to set the timing when you replaced the timing guides that is your problem right there.

I have the factory timing tools and Besian vanos repair kit. I have acutally done this job 4 times now.

1999 540iT
2001 X5 4.4
2000 540 M Sport
2002 X5 4.6is

On both the wagon and the 540 M I got cam timing errors on one bank when I first started them up. I believe they both said timing over advance and signal not plausible. I first tried retarding the pickup wheel and when that didn’t work I actually had to advance the timing wheel in each case about 1/16" from the factory set point on the error bank to make them work. Both cars run very smooth after that. I still have the 540 M Sport. I think I will hook the computer to that as see what the cam angles are at for comparison. Actually I think I had to do the same thing on the X5 4.4

On this 4.6is i have them set exactly to the factory spec. I lined up the wheel with a tight fitting drill bit through the upper timing chain cover hole. I couldn't get them right on with the tools because of too much play in the way they mount.

[upallnight]

I hope that you are aware that there are two cam locking tools and they are specific for each bank of the engine so you can't interchange the two locking tools. The tool will fit but if you have the tool on the wrong bank it will throw off the timing.

here's a video on what I am talking about.

https://www.youtube.com/watch?v=8nIGZW-K2oY

[murf]

Originally Posted by upallnight

I hope that you are aware that there are two cam locking tools and they are specific for each bank of the engine so you can't interchange the two locking tools. The tool will fit but if you have the tool on the wrong bank it will throw off the timing.

here's a video on what I am talking about.

https://www.youtube.com/watch?v=8nIGZW-K2oY

Thanks for the heads up on that. My cam locks have the cylinder banks etched on the top, so hard to mix them up.

[murf]

The cam adaption angle being out of spec I think is trying to tell me something.

The values are supposed to be between -5 and +5 degrees on bank 1 and -5 and +4 on bank 2.

I will put the computer on my 540 and see where those are. Then I guess I will have to experiment turning the timing wheel one way or the other to see if I can get the values in spec.