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What solenoids did you install, & did you reset the adaptations on the engine. This will make a ig difference. What ever your problem is, it is part of the Vanos system sensors. Disconnecting the MAF & running better, verifies this.
How can a VANOS solenoid go bad just because the car had been sitting for a year ? Sure the oil could of drained out of it, but a few miles of hard driving would soon fix that. The ICV controls the idle speed not the VANOS.

IF like OP states the engine is fine after idle and drives well, then VANOS is functioning.
Alot of water tends to accumulate in cold engines when the heat is not there to evaporate it all out the tail pipe. Disconnecting MAF just proves the issue is with fuel trims as a fixed default fuel map is then used.
 

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How can a VANOS solenoid go bad just because the car had been sitting for a year ? Sure the oil could of drained out of it, but a few miles of hard driving would soon fix that. The ICV controls the idle speed not the VANOS.

IF like OP states the engine is fine after idle and drives well, then VANOS is functioning.
Alot of water tends to accumulate in cold engines when the heat is not there to evaporate it all out the tail pipe. Disconnecting MAF just proves the issue is with fuel trims as a fixed default fuel map is then used.
I didn't say a Vanos solenoid went bad, but sitting for a year can keep it from operating properly. If he cleaned the solenoids & that didn't help, that is the next logical step. Unplugging the MAF sensor puts the mapping for the Vanos system in a safe mode, to make help the engine run to get the car where ever it is going. The engine want have full power, but it will run without mass hesitation. All of the cam sensors, Eccentric Shaft sensor, & the Vanos solenoids, are part of the Vanos system. Any failure in any of these sensors, takes the Vanos system down. When this happens, your timing is all out of phase, & the engine will stumble badly. I just encountered 2 weeks ago, that new & bad Vanos solenoids, can even effect the oil pressure on the engine. The Vanos solenoids controls the oil flow throughout the top end of the motor, & what part of the engine gets the correct amount of oil. If the solenoids are not configured properly, they can even make the oil pressure light go off at idle! The Vanos system is part of this engine, that controls more than you would think!
 

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I didn't say a Vanos solenoid went bad, but sitting for a year can keep it from operating properly. If he cleaned the solenoids & that didn't help, that is the next logical step. Unplugging the MAF sensor puts the mapping for the Vanos system in a safe mode, to make help the engine run to get the car where ever it is going. The engine want have full power, but it will run without mass hesitation. All of the cam sensors, Eccentric Shaft sensor, & the Vanos solenoids, are part of the Vanos system. Any failure in any of these sensors, takes the Vanos system down. When this happens, your timing is all out of phase, & the engine will stumble badly. I just encountered 2 weeks ago, that new & bad Vanos solenoids, can even effect the oil pressure on the engine. The Vanos solenoids controls the oil flow throughout the top end of the motor, & what part of the engine gets the correct amount of oil. If the solenoids are not configured properly, they can even make the oil pressure light go off at idle! The Vanos system is part of this engine, that controls more than you would think!
Yeah, sitting without oil circulating can require it to be primed a little longer, but wouldn't cause it to fail.

The VANOS don't work like that, it is more for improved MPG than performance. The oil pump controls oil pressure not the VANOS which just uses oil pressure. VANOS is always in safe mode when the engine is shutdown. Engine will run quite well with all VANOS solenoids disconnected, why dont you try it yourself ?
I have and all that was affected was mid to high-end torque, but not enough to cause the engine to misfire. Not sure why you got the idea that a VANOS solenoid can affect oil pressure.

I've had P0014 DME codes for VANOS which deactivates the VANOS. Engine performace is much lower but is still smooth and does not misfire. The code is misleading as it also usually appears with a camshaft P0011 or P0012 code. Turns out nothing to do with VANOS and is a cam sensor fault, elcheapo cam sensors can also cause this. Sometimes a stuck/faulty VANOS solenoid can be the cause but would certainly not cause the engine to misfire, just affect the optimal timing for the current RPM speed.
 

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I just went thru a motor rebuild due to Vanos problems. The oil pressure would drop to 5 psi, & at that point I shut the engine down. I took the motor back out & double check everything, & still had oil pressure problems. I installed 4 new Vanos solenoids after all of this, & the oil pressure got better, but still had low oil pressure at 8 psi. I then removed all of the solenoids & the valve covers again, & their was plenty of oil in the heads, but the oil pressure would not hold. After spending weeks of reading & scratching my head I was at a loss. I have a manual pressure gauge installed, to make sure what I was seeing? I finally got 12 psi after finding an additional o-ring that was installed on the solenoids that blended in with the solenoid. This o-rings were on 3 of the 4 solenoids. The green o-rings were in the box & installed when I received them. After finding this problem, I was sure that this was my problem, but 12 psi after a rebuild this was not good for me. I finally reset the adaptations on the Vanos solenoids, & watched my oil pressure jump to 18 to 20 psi at operating temp. I was totally at a loss when this happened, as the gauge was directly in front of me. I was pleased and shocked, that the Vanos solenoids control this much oil & direction, to effect oil pressure like this. Since this the oil pressure has held. There are many people out their with oil pressure problems with our engines, & install a lower psi switch. Not one person ever stated what caused or fixed this problem. Look at all the info you can find on the net, & study & understand how the Vanos solenoids control the oil. Until you do this & go thru this, you will never understand the Vanos system. If it can't control the oil flow, the engine will not run correctly. Yes you can put the Vanos system in safe mode to operate the vehicle, but if the solenoids are not controlling properly, you can trash the engine very fast!

Do some reading!
 

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When you disconnect the MAF., the DME switches to a fixed AFR map- which I believe is richer than normal…

If you have an intake leak and are sucking some air, when you disconnect the MAF and it used the richer map, it runs better- at least on idle and initially.

At least w some BMWs. I’ll defer to those here with better model specific insights.
 

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. Disconnecting the MAF & running better, verifies this.
I will add that if the issue is a sluggish Vanos that isn’t hitting the right cam position at idle, it may ‘like’ the ‘no MAF map’ you get when disconnected…
 

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I will also add that old oil sitting in narrow/small places (like inside a Vanos solenoid) can get gummy over time…
 

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I just went thru a motor rebuild due to Vanos problems. The oil pressure would drop to 5 psi, & at that point I shut the engine down. I took the motor back out & double check everything, & still had oil pressure problems. I installed 4 new Vanos solenoids after all of this, & the oil pressure got better, but still had low oil pressure at 8 psi. I then removed all of the solenoids & the valve covers again, & their was plenty of oil in the heads, but the oil pressure would not hold. After spending weeks of reading & scratching my head I was at a loss. I have a manual pressure gauge installed, to make sure what I was seeing? I finally got 12 psi after finding an additional o-ring that was installed on the solenoids that blended in with the solenoid. This o-rings were on 3 of the 4 solenoids. The green o-rings were in the box & installed when I received them. After finding this problem, I was sure that this was my problem, but 12 psi after a rebuild this was not good for me. I finally reset the adaptations on the Vanos solenoids, & watched my oil pressure jump to 18 to 20 psi at operating temp. I was totally at a loss when this happened, as the gauge was directly in front of me. I was pleased and shocked, that the Vanos solenoids control this much oil & direction, to effect oil pressure like this. Since this the oil pressure has held. There are many people out their with oil pressure problems with our engines, & install a lower psi switch. Not one person ever stated what caused or fixed this problem. Look at all the info you can find on the net, & study & understand how the Vanos solenoids control the oil. Until you do this & go thru this, you will never understand the Vanos system. If it can't control the oil flow, the engine will not run correctly. Yes you can put the Vanos system in safe mode to operate the vehicle, but if the solenoids are not controlling properly, you can trash the engine very fast!

Do some reading!
Total rubbish, VANOS can be disabled completely and the engine can run without it, was designed that way. Was the oil pressure measured correctly because you didn't state how or where you measured it or if you used the correct BMW oil pressure test tools and procedure. Oil pressure increases with RPM so will be lower at idle and VANOS doesn't kick until high RPM. Go through the BMW TIS again Pal. The VANOS solenoids are not the engines oil pump which is why the oil pump is called an oil pump and is why location is at the bottom of the engine and not the top like the VANOS solenoids. You probably know this already, but it's there so others can take note of it. Your oil pump or oil pressure relief valve failing and lack of oil would trash your engine, are you sure it wasn't one of those casuing you to rebuild the motor. ;).
 

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I will add that if the issue is a sluggish Vanos that isn’t hitting the right cam position at idle, it may ‘like’ the ‘no MAF map’ you get when disconnected…
I agree with you on that, VANOS operation starts within 2-3 seconds of engine start and can affect idle if MAP disconnected without that signal. If DME detects a problem within 2-3 seconds of ignition, VANOS can also shutdown and engine performance would be very flat as cam timing cannot adjusted optimally. This would not cause any misfires but would appear like a misfire to those who don't know whats happening. Engine will have reduced torque as engine RPM is increased. Depending on the DME version an ECL or "limp" mode may also be activated.
 

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I agree with you on that, VANOS operation starts within 2-3 seconds of engine start and can affect idle if MAP disconnected without that signal. If DME detects a problem within 2-3 seconds of ignition, VANOS can also shutdown and engine performance would be very flat as cam timing cannot adjusted optimally. This would not cause any misfires but would appear like a misfire to those who don't know whats happening. Engine will have reduced torque as engine RPM is increased. Depending on the DME version an ECL or "limp" mode may also be activated.
VANOS solenoids that are slightly fouled with oil/sludge/crap can cause odd issues. They arent necessarily 'bad' such that they trip electrical errors...and they may, EVENTUALLY get to their commanded positions so the DME doent set 'camshaft position errors'...but their sluggish operation means the timing advance the DME THINKS it has, isnt really there...which in highly tuned motors will lead to transient AFR issues and overall poor performance. Think S62.
 

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I will add that if the issue is a sluggish Vanos that isn’t hitting the right cam position at idle, it may ‘like’ the ‘no MAF map’ you get when disconnected…
This happened with old Vanos solenoids after the rebuild. The oil pressure got down to 5 psi several times. Out comes the motor looking for the problem. There were 2 bearings that were slightly wiped, & replaced. Everything else looked very good. I put the motor back in, & had the same problem! I install 2 Vanos solenoids & the pressure started to rise, but still got down to 5 psi. I installed 2 more Vanos solenoids & the pressure increased to 12 psi. I still felt there was something wrong, but I couldn't put my finger on the problem. After days of watching this happen & watching the oil pressure gauge I installed, I then went ahead I reset the adaptations for the Vanos solenoids. Magically the oil pressure jumps from 12 psi, to 18 psi to 20 psi while I am watching ISTA & the OP gauge.. This is well within spec, & then I finally found the problem. I new I needed to reset my adaptions on the complete engine, but I wanted to solve the OP problem before I reset everything. I learned a lot from all of this the hard way. I even talked with AGA asking for help, & he suggest a 15w40 oil, as this is the easiest way to fix the problem. Search oil pressure problems on the 4.4 & 4.8 engines, & no one never really understood how to solve the problem. Either people installed a lower setting OP switch to get around the problem, or the installed the 15w40 oil. As being a Reliability Engineer I have always sat down & worked thru problems with multiple high tech tools, & pinpointed any problem. I di not have those tools at my disposal since I retired, but the never would have solved this problem. The Vanos system is the most complex system on theses engines, as the control the timing, torque, & oil pressure on the engine. Below are pics from the N62 PDF, & how they work. I am not sure if many people ever sit down & read this part in detail?


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Total rubbish, VANOS can be disabled completely and the engine can run without it, was designed that way. Was the oil pressure measured correctly because you didn't state how or where you measured it or if you used the correct BMW oil pressure test tools and procedure. Oil pressure increases with RPM so will be lower at idle and VANOS doesn't kick until high RPM. Go through the BMW TIS again Pal. The VANOS solenoids are not the engines oil pump which is why the oil pump is called an oil pump and is why location is at the bottom of the engine and not the top like the VANOS solenoids. You probably know this already, but it's there so others can take note of it. Your oil pump or oil pressure relief valve failing and lack of oil would trash your engine, are you sure it wasn't one of those casuing you to rebuild the motor. ;).
Suck it up & read how the Vanos system works on our engines. I rebuilt the oil pump & tore it down twice for inspection. Disabling the Vanos system, only effects the timing, not the oil pressure! The Vanos system controls more than you think, se read the reply above!
 

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Disabling the Vanos system, only effects the timing, not the oil pressure!
I know, that's exactly what I was pointing out to you. Read teh description for item "A" in your diagram. I don't see where it states "Oil pressure from VANOS". Still have not stated how or where you measured the oil pressure.
 

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If you follow the path from the oil pump, everything in the heads come thru the check valves. The intake & exhaust Vanos solenoids control the oil from that point. As the solenoids are changed & controlled from the DME, the exhaust path feeds the oil pressures switch & the timing chain tensioner. These 2 item only get oil thru the solenoids. The path of the oil from the oil pump, go directly thru the heads. 3 check valve, 1 for the lubrication of the heads, & the other 2 thru the Vanos solenoids. If you remove the OP switch & add a T, you can measure the oil pressure from there with a analog gauge. There are only 2 places to measure the oil while the engine is running. One is the oil pressure switch port, & the other is from the bottom of the oil filter. The 2 places will differ by a few pounds, but they should be within 2 psi. It sounds like you have never had the engine apart, & actually looked at all the possibilities of how the oil ports operate. It is really not as hard as you make it, you simply don't understand how the Vanos system operates, & how it controls the oil from the Vanos system. For most people it works or not, but they never try to understand how it operates.
 

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If you follow the path from the oil pump, everything in the heads come thru the check valves. The intake & exhaust Vanos solenoids control the oil from that point. As the solenoids are changed & controlled from the DME, the exhaust path feeds the oil pressures switch & the timing chain tensioner. These 2 item only get oil thru the solenoids. The path of the oil from the oil pump, go directly thru the heads. 3 check valve, 1 for the lubrication of the heads, & the other 2 thru the Vanos solenoids. If you remove the OP switch & add a T, you can measure the oil pressure from there with a analog gauge. There are only 2 places to measure the oil while the engine is running. One is the oil pressure switch port, & the other is from the bottom of the oil filter. The 2 places will differ by a few pounds, but they should be within 2 psi. It sounds like you have never had the engine apart, & actually looked at all the possibilities of how the oil ports operate. It is really not as hard as you make it, you simply don't understand how the Vanos system operates, & how it controls the oil from the Vanos system. For most people it works or not, but they never try to understand how it operates.
VANOS solenoids DO NOT control the oil pressure throughout the engine! The the oil pressure in/from the VANOS is not part of the oil pressure to the engine. VANOS uses oil pressure delivered from pump! Stop thinking your idea of how it works, BMW wouldn't engineer such a system. You still didn't state where you measured the oil pressure. The diagrams are just simplified operation pictures, I dont need to be educated by clipart Pal. But clearly you do, so look at your clipart of the engine and you can clearly see the RED main oil channels are completely seperate from the GREEN vanos channels. A restriction or drop in pressure in the GREEN channels would not affect the RED or BLUE channels. There you are, I made it as simple to understand.
 

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If you would read the entire post, it will say where I measured the oil pressure from! I didn't say the Vanos system controls the oil to the complete engine, just the heads! There are 3 check valves that receive oil from the oil pump, then the Vanos system controls the oil supply from 2 of the 3 check valves. At that point the DME controls the Vanos solenoids & distributes the oil based on the engines demand for timing. If the diagrams were simple, it seems that you might understand them more clearly?
 

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If you would read the entire post, it will say where I measured the oil pressure from! I didn't say the Vanos system controls the oil to the complete engine, just the heads! There are 3 check valves that receive oil from the oil pump, then the Vanos system controls the oil supply from 2 of the 3 check valves. At that point the DME controls the Vanos solenoids & distributes the oil based on the engines demand for timing. If the diagrams were simple, it seems that you might understand them more clearly?
VANOS solenoids DO NOT affect the oil pressure to any other part of the engine other than the vanos and like we both agree to control the cam timing. That's the only job the vanos is there for, to control or distribute the oil pressure to the vanos pistons! (NOT THE ENGINE). The solenoids are pulse driven by the DME to control the oil flow. There isn't really anything to understand just use a little common sense. Study your oil circuit diagram! The RED and BLUE engine channels will not be affected by any restriction or low oil pressure in the GREEN vanos channels. Even the chain tensioner is within a RED channel so explain how that could be controlled by the vanos.

This is getting a bit pointless now as I only wanted to point out to you that a non functioning vanos would not blow up your motor by causing low oil pressure. Why would you think that and argue that it would? Sure driving around with a vanos fault would not be good for the engine in the long run, but the motor wouldnt give up from low oil pressure. Would foul the plugs and burn up your cat and wallet before the motor.
 

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Okey doke. When is Vanos supposed to advance the timing and by how much. My general impression is that the advance comes in way too late. How far up on the cam do you have to get before this gets good? Or does it?
 

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I hope one day one day you get to experience this in your own motor, & get to rack your brain out! The exhaust Vanos solenoid feeds the path to the oil pressure switch & timing chain tensioner. I will let you figure out how this is done, since I already know. The exhaust Vanos solenoid always controls the engine at idle, & the intake solenoid takes over when the advance in timing is as needed. The DME controls all of this as needed based on all of the other sensors on the engine.. The oil from each Vanos solenoid feeds the Vanos motor or drive, thru the #1 bearing cap on each camshaft. Excess oil is then sprayed onto the valve springs for lubrication. If the oil does not pass thru the solenoids, the cam bearings will be starved, along with damage to the bearing bores. This will also effect the oil pressure at the oil pressure switch, as no oil means low oil pressure. At idle I think you will see around 12 to 15 degrees of timing.

I am done wasting my time with this, so think what you think!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 
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