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Discussion Starter #1
Hi guys,

So last summer I got my vanos tested with DIS. On bank ONE, the test failed, and got these results:
935959


So while the car is in storage for the winter, I decided to tackle cleaning the boards and replace the solenoid seals.
It all went smoothly. I've cleaned the solenoids with compressed air and MAF cleaner. They would all open with 12v applied to them.

I rant the test again after the work, a while the numbers seems to have improved, I still fail the inlet test:
935960



The car runs ok. No CEL. A little rough idle when it's cold, but other than that. Nothing really noticeable.

So what should I do next? I'm assuming one of the solenoids needs replacement, but which one? Maybe it could be something else ?
 

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Discussion Starter #2
I forgot to mention, and maybe it has nothing to do with this, but while the bank2 solenoids were rather clean, two of them on bank one had some kind of hard to clean carbon-like deposits on the outside....
 

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Discussion Starter #4
Thanks. Amazing. I've been looking to buy boards or solenoids and prices are just crazy.

Do you know by any chance which two solenoids are for the inlet located on the board?
 

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Discussion Starter #6
Ok, so if I understand correctly, I should be looking at solenoid 1 or 2 on bank1??
But no way to know which one need replacement exactly?
 

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Yes, solenoids 1 or 2 but I can’t say which or both for sure. Others might have a better idea.

In my case, I had a bank 1 exhaust code for over retardation that went away when I swapped the solenoid boards from bank to bank. When swapped, the solenoid functions are swapped not only intake and exhaust but oil flow inlet and outlet. I guessed it was the original exhaust outlet solenoid since inlets are less picky on leakage (why the problem went away when swapped). When I replaced the suspect solenoid and swapped the boards back, the code went away. I’m not sure you would be able to deduct the same way with your current scenario.
 

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Discussion Starter #8
Thanks for your help. I've cleaned the boards a little more with seafoam this time (great product) and switch them sides. I thought as you said that inlet would become exhaust and vice versa, but it seems that the leak remained on the same location.... (inlet)

It failed the first time at 5.4cr, but on a second occasion that's what i've got:
936093


Well it's not close to 0, but at least within the specified values. So i'll drive it like that for this year and will check next winter. Hope it will make a difference!
 

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I think the best way to clean the pintle and/or seat in these solenoids is by ultrasonic cleaning. Also, if you repeat the tests back-to-back, does the number get worse?
 

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Discussion Starter #10
Went from 12cr to 8cr after one cleaning, and then 5.4 and 4.6... so it seems to improve.

I do have an ultrasonic cleaner, but I was not really sure if it's a good idea to throw the board in there. You did it with success? You removed the solenoids from the board? (unsoldered?)
 

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Went from 12cr to 8cr after one cleaning, and then 5.4 and 4.6... so it seems to improve.

I do have an ultrasonic cleaner, but I was not really sure if it's a good idea to throw the board in there. You did it with success? You removed the solenoids from the board? (unsoldered?)
I have not ultrasonically cleaned mine, but I believe DrVanos uses this technique to clean the units they refurbish. Chris @ DrVanos is usually quite responsive to questions. I'm not sure if they remove them completely, or set them down intact, operating the solenoid in the bath.
 

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You said you switched the boards side for side and the fault still remained. Your problem is likely the vanos piston seal or some where else in the system. On bank one it can also simply be a weak chain tensioner as all the slack goes there.
Before I get excited about bank one issues I generally just change out the tensioner because I have a new or known go one floating around. If you have never changed that part it is still good to replace it. They seem to be the known cause of early chain guide failure.
If that does nothing then I simply jump in the car and keep the car from dropping the RPM below normal idle during the test. If that allows the car to pass, it tells me whatever leak I have is minor and I should not be too concerned. The piston seal can be replaced but it is a different type and it takes some time for the new to wear in. I avoid that until it is really required.
Also don't rule out that a minor running issue at idle could bring the idle just low enough that vanos pump puts out a little less pressure and causes this fault. Again if keeping the rpm up helps pass the test you might want to look for air leaks or other common maintenance items on these old cars.
 

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Discussion Starter #13
I may have not clearly explained what occurred.
The board is most likely the culprit, because the fault went from bank 1 to bank 2 when I switched them sides. But I was expecting the inlet fault becoming the exhaust and vice versa, but that wasn't the case.

Not sure if i'm interpreting this the right way, but i went from 12.3ccr to 4.6ccr... it's gotta be a significant improvement?
 

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Ok my bad you said the error remained in the same location but you meant that it switched sides but you got an intake error not not an exhaust. You need to clean them again but use the correct tools or products. There is nothing in seafoam that makes it a good cleaner. Just do the searches and skip the testimonials and look for the posts that include the MSD and what that says.
Not prepared to go down that road again but if there was something special in it, it would say in the old MSD reports that did not allow some blanket statement that was company secret. If there was something special in it then it would have been in the pre 2018 MSD.
Besides that, nothing special is required to clean the noids but sometimes it takes some acid or strong base to chew up what is left of the filter. The filter strands can get lodged in the noid and have a very difficult time coming out.
If there are strands stuck in the noid you must use a compressor in the cleaning process. If you did not use a compressor, rent one and try again. Take the noids out is best take a tooth pick and open the pintle leaving the tooth pick in to keep them open, soak them over night in kerosene, diesel or even seafoam since all it is is a light oil that absorbs water.
Once you have done that turn up the compressors output to the max, blow from the side hole mainly but stuborn ones require the odd blast from the tip to loosen the stands up. Put it back together and try it. If you get an intake error switch the 2 intake noids with each other. The difference in the two reports will tell you which of the noids is still dirty but unlikely clean able and you can replace it.
Likely all you need is a good cleaning of the noids, most people doing the noid cleaning did not get it right on their first try.
 
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