1997 540i manual not smooth on 1 bank

[R Shaffner]

Thx. As I understand it the LTFT will adjust over time based on the STFT. I think the LTFTs for both banks are around zero because everything was just reset. If the STFT stays around -8 for bank 2 long enough then the LTFT will move toward -8 and as it does (without any other changes) the STFT will move toward 0%. That would still mean a net -8% for that bank. (Since the LTFT was already moving to -2, the real total number now might be -10.)

Of course, those readings are soon after the reset, and perhaps mostly at idle. They might all change as you drive. (It's worth checking them again after driving a while, before you reset it again.)

[R Shaffner]

One more thing and please don't be offended by this...

Just this week I saw an experienced elevator technician get so frustrated with a stuck bolt that he twisted the head clean off. As it happened, he was approaching it from an unusual angle and was trying to tighten it, instead of loosening it.

The title of this thread says you have roughness in bank 1, but most of the rest of this refers to problems and fixes for bank 2 and cylinders 5-8. Which is it?

You might want to double check what BMW means by banks and cylinder numbers, just to make sure something hasn't gotten turned around. (It can happen to anyone.)

[R Shaffner]

bfrqrv: I apologize for questioning whether you had the correct side, etc. Looking back at your pics it appears you have.

Yeah, if I were you at this point I'd pull the bank 2 cam cover and check the cam timing. It's all friction -- easy to see how something could slip during the work or after. I'd put in a crank pin at #1 TDC. Then I'd see if a straight edge can touch (link) both timing marks on the bank 2 intake and exhaust cams. (Or see if cam blocks fit, if you have them.)

There IS a way to adjust the cams without removing the upper timing chain cover. I can go over that if there's a need.

Good luck.

[bfrqrv]

Sorry for the late response, it was a stupid mistake! I keep this page open in the browser and refresh it each day. But it stays on page 2 and the response was on page 3. Stupid.
I have some new findings and conclusions. Lets see if it fits in your ideas. I have the timing on the longlist, but the shortlist is almost finished.

Today I took of the manifold again to look at the intake valves. Cylinder 1,5,8 and 4 has 1 valve black and 1 valve clean. My worst cylinders are 1,5 and 8. But cylinder 4 is the best cylinder and does have 1 black valve.
I really think that the cause of this must be that the injectors doesn't spray correctly out of the 4 small holes. The spray pattern is screwed, so there isnt getting any fuel in that part of the manifold, and the valve isn't cleaning itself.

Second thing is how do the valves get carbonated. I think I have found it. I did clean the pcv and did a new gasket there. But I forgot to to the big o-ring that is between the pcv and the manifold. I try to get this on pics so you see what I mean.
Without this o-ring the oil will not go through the pipe that is inside the manifold and goes out of the manifold. The oil will come in the manifold housing and will be sucked to the intakes.

I try to get this clear with some pics. Here you see 2 clean valves but the oil is there. But because of the injector is spraying correct the valves stay clean.

1.jpg

Here is the pic with the same oil but the injector might not spraying that good

2.jpg

Here is the pcv

wet enviroment 2.jpg

And here a small video about the connection between the manifold and the pvc I talk about.

http://www.blackshalo.com/oil.mp4

I hope I explained it clear. I think when I replace some more injectors and replace the o-ring so there isn't getting any oil within the manifold the smoothness will become better. I think the excessive oil will trick the ecu thinking it is rich on that bank also.

[R Shaffner]

Interesting idea, to examine the intake valves as an indicator for the misting and direction of the fuel spray. It'a certainly possible that poor spray could affect combustion, and might have a larger effect at idle.

About the source of the carbon build-up... Yes, that's from oil and blow-by (partially unburned) gasses. The O-ring you're referring to has oil on it because that's the path for blow-by gasses, with some oil vapor, to go into the intake and get completely burned.

However, that O-ring has nothing to do with the amount of oil vapor or blow-by entering the intake. It just sends them to the front of the manifold where they get mixed with the air coming from the TB to get distributed evenly to all the cylinders. (As I understand it the M60 didn't have that tube inside the intake and most of the oil/blow-by went to the rear cylinders.

In other words, as it is now the blow-by gasses and oil vapor should be getting to all cylinders pretty evenly. The variation in deposits on the intake valves would be from the fuel spray or lack of it, not because some cylinders are getting more/less blow-by oil.

There are ways to reduce or eliminate the blow-by/oil to the intake. For starters you could vent those to the atmosphere (and pollute it a bit more). Or one could install a secondary OSV or oil catch can to filter the oil twice -- a lot of effort for some unknown added benefit.

In any event, the engine can run fine and smooth (both banks) with a normally functioning OSV and CCV system.

[R Shaffner]

Also, I don't see a clean sealing surface all around those ports on the head. Are you sure those intake gaskets weren't leaking?

[bfrqrv]

Interesting idea, to examine the intake valves as an indicator for the misting and direction of the fuel spray. It'a certainly possible that poor spray could affect combustion, and might have a larger effect at idle.

About the source of the carbon build-up... Yes, that's from oil and blow-by (partially unburned) gasses. The O-ring you're referring to has oil on it because that's the path for blow-by gasses, with some oil vapor, to go into the intake and get completely burned.

However, that O-ring has nothing to do with the amount of oil vapor or blow-by entering the intake. It just sends them to the front of the manifold where they get mixed with the air coming from the TB to get distributed evenly to all the cylinders. (As I understand it the M60 didn't have that tube inside the intake and most of the oil/blow-by went to the rear cylinders.

In other words, as it is now the blow-by gasses and oil vapor should be getting to all cylinders pretty evenly. The variation in deposits on the intake valves would be from the fuel spray or lack of it, not because some cylinders are getting more/less blow-by oil.

There are ways to reduce or eliminate the blow-by/oil to the intake. For starters you could vent those to the atmosphere (and pollute it a bit more). Or one could install a secondary OSV or oil catch can to filter the oil twice -- a lot of effort for some unknown added benefit.

In any event, the engine can run fine and smooth (both banks) with a normally functioning OSV and CCV system.

Good information. I was not totally sure about the exact working of the crankcase ventilation system for the non vanos m62. I saw the o-ring was bad so I guess a new one is good to go.
I also ordered the new injectors.

The intake gaskets are new and I had this oil on the surface also with the older gaskets that where 2 years old. So every new gasket leaves oil on the head surface except at cylinder 4.
I use 22NM for the intake bolts and I am sure it's fitted with care.

Secondly, can you somehow make a picture or so from how exact the vapor/oil and air goes on this crankcase ventilation system? I try to imagine where it all goes and what exact the OSV inside the engine does, and the PCV outside the engine. When I know the exact work and directions I can diagnose the oil residue better I guess.

[R Shaffner]

Check out this thread:

https://www.bimmerforums.com/forum/s...=m62+catch+can

It's a good practice to clean all surfaces you want a gasket to seal.

[bfrqrv]

I think this part is more important then we think:

"However, that O-ring has nothing to do with the amount of oil vapor or blow-by entering the intake. It just sends them to the front of the manifold where they get mixed with the air coming from the TB to get distributed evenly to all the cylinders. (As I understand it the M60 didn't have that tube inside the intake and most of the oil/blow-by went to the rear cylinders."

When that O ring is bad the oil will gather at the front of the intake and will get sucked into the intake manifold ports. That is not the original plan of the manifold.

I fitted a new o-ring and placed the manifold back on the head. Next week I will change all 4 injectors on bank 2. I couldn't clean the intake valves, but with the knowledge that my favorite cylinder 4 has also a black valve, I hope the smoothness can be good with some valves carbonated.

[bfrqrv]

bfrqrv: I apologize for questioning whether you had the correct side, etc. Looking back at your pics it appears you have.

Yeah, if I were you at this point I'd pull the bank 2 cam cover and check the cam timing. It's all friction -- easy to see how something could slip during the work or after. I'd put in a crank pin at #1 TDC. Then I'd see if a straight edge can touch (link) both timing marks on the bank 2 intake and exhaust cams. (Or see if cam blocks fit, if you have them.)

There IS a way to adjust the cams without removing the upper timing chain cover. I can go over that if there's a need.

Good luck.

Ok all done and without any results. Now I have done all possible things except checking the timing on bank 2.Maybe the garage has set the timing exact on the place how it was before the chain guide replacement and is it slightly of.
Do yo have a good tutorial on how to check (in first instance) the timing for the non vanos M62? I have no experience with these timings, so I need some written tutorial on how to get there, then I am certain I can manage it.

[R Shaffner]

The concept is real simple, but you need to take a few steps to make sure it's right.

Steps:
1) Remove the cam cover.
2) Rotate the engine until #1 is at top dead center (TDC). At that point you should be able to put in a crankshaft locking pin. You'll know its near TDC by looking for marks on the cams that should be pointing up and out, 90 degrees from the head surface. Here's a picture that will help:
cams_cyl1_tdc2.jpg

You should be able to use 2 reference points. Toward the middle left in this picture you can see the cam marks that should point up and out, away from the head when #1 is at TDC. In this picture the intake (top) cam has one dot and the exhaust (bottom) cam has three. If the timing is right, at #1 TDC you should be able to put a straight edge across both cams and have it touch squarely on both marks.

At the right in this picture, where it says 58 on each cam, are the fitting for cam timing blocks. Of course if you have those or can rent them, that's a great way to make sure the cams are in proper alignment at #1 TDC.

If you find them out of alignment, you CAN adjust one or more without removing the upper timing covers. The process is to remove the crank locking pin, turn the engine forward 360 degrees so the cams are upside down from this picture, loosen three locking bolts holding the sprockets to each cam, turn the engine forward again 360 degrees (MAKING SURE THE CAMS MOVE WITH THE SPROCKETS), loosen the other 3 bolts on each cam sprocket , put in the locking pin, adjust the cam(s), and re-tighten those bolts. Remove the pin, then turn the engine forward another 360 degrees and tighten the remaining cam sprocket bolts. Turn it forward another 360 degrees, put in the locking pin and recheck your timing. Repeat if needed. Remove the pin.

Then replace the cam cover.

[bfrqrv]

I checked the timing and it's ok. Thank you for the nice and short tutorial.
Today I captured the difference between with and without O2 sensors. Pre cat. There is a bgi difference for sure. You can almost say buy a new sensor, but there is one thing that is bordering me.
Isn't it so that the engine has to be running totally smooth with and without O2 sensor? In he morning when it's cold the sensors are deactivated and the engine roughness is there on INPA. When I drive it warm and I plug-in INPA again it's still rough.
When I disconnect the O2 sensors then it smooths out a bit.

with sensors:

IMG-20190810-WA0009.jpg

without sensors bank 1 and bank 2:

IMG-20190810-WA0007.jpg

[DnyCe220]

Ever figure this out?