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Discussion Starter #1 (Edited)
I was wondering if anyone else has had this code come up, yet running the VANOS tests in DIS passes all tests.

Could this still be a solenoid, even though the tests pass?

I pulled the code using INPA, cleared them, drove the car until test conditions were as instructed, run the VANOS DIS 5.7 tests and everything checks out.

I'm leaning to a CPS at the moment, but I'd like to hear some opinions on the matter.

Thanks all!

PS I've read everything here on the maintenance and CPS swap; I figured the CPS was the easiest at this time.
 

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You will likely find you have a shorted/failed MOV or one has fallen off. The MOV basically allows for control of the solenoid because it absorbs the electricity created when the solenoid closes. That electricity can hold the noid from closing when it should. In the DIS tests the noids are set to max open to test the stops or maximum position, it does not test for accurate placement of the cam.

If you unplug that board and test the leads for Ohms likely you will find three read 3-4 ohms but one will be 0. Even if they all read 4 you may have a MOV fallen off or burned out and not closing the noid when it should. You can find a short but the only way to see if one has fallen off or burned thru is to pull the cover and look.

With the black lead from the meter on #2 pin check the red lead on 1 and then 3, that should be enough that is the intake but for fun move the black to 5 and test 4 and 6.
Vanos Board Schematic_V3.jpg
 

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Discussion Starter #3
So it is still possible to have a solenoid issue, even with the VANOS tests all passing. This is interesting, thanks for the graphic, it helps quit a bit. Thanks, Sailor.

I'll remove them this weekend and test them. I have had the gasket kit for a few weeks and planned on doing the maintenance and remove the screens and what is left of the gauze material ... then this code showed up and the car runs well.
 

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You don't have to remove them. The circuits are all on the backside. I would test/inspect in the car just by unplugging first to get an idea. Not sure why but every MOV issue I have faced had a second try and trick me at the sometime.

This is an electrical issue not a solenoid issue but you will likely find improvement to the whole system after the maintenance.
 

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Discussion Starter #5
So what controls the DIS v5.7 VANOS tests? Could it be they all pass, yet there is still an electrical issue causing the b8 code?

I will examine from the outside today for sure and I still intend to replace the rings as well.
 

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That is what I was trying to explain the test only tests the max, really it is a hydraulic test and static timing test. You can even have some leaks and pass the test, not big leaks, and only on one side, don't remember which though. If you had a failed solenoid you would likely fail but a dead move is really just a control issue.

Definitely do all the work but if you do it a step at a time you will be less likely to miss something. A lot of first timers end up being second and third timers on board maintenance. It seems easier that it is. It is not hard just a lot people miss. Like for one on reassembly people don't turn the noids so the wires are tight and pinch a wire when the cover goes back on. People also grab the wire when trying to remove. Knock MOVs off the board.
 

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Discussion Starter #7
I've replaced the d-rings on all the solenoids, removed the plastic screens (they were already cracked) and did the 'click' test using a 9v battery. They all click with the same pitch and sound good. Replacing the board and firing up the car, I still have the b8 code as well as 1 each of a 43 and 48. I loaned out my multimeter until Monday so when I get it back, I can measure the resistance across the MOVs. The CPS will arrive Tuesday, fwiw, I've seen some posts where the CPS is the possible culprit for these VANOS codes, especially b8.

Thanks for your help, Sailor, I hope to have some more data early in the week.
 

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The 43 and the 48 mean the DME has lost contact with the two intake cam solenoids on bank 1 due to a wiring fault. Try the DIS VANOS test again.

Malcolm
 

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Too bad you don't have your meter we could figure it out in less than a min. Remember I said second and third timer. This sort of looks like something else than a normal pinched wire. It looks like you lost the ground somewhere from the board to the plug or in the plug maybe even back to joint X6881. I only remember that number because of the number of failures.
Could be CPS but I doubt it. When CPS are the cause of a position code they are slow to come and is more intermittent for lack of better word.

Maybe if you have time and the desire. Pull the boards and switch sides that will tell if it is board related. When you have the boards out look close to see why the ground is gone. When you switch sides the codes will be for exhaust bank 2.
 

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Discussion Starter #10
I never seem to have my multimeter when I need it :) I only have desoldering braid too, I've not heard folks here using that to remove the solder if needed so I'll order one of those vacuum removal tools from amazon and it will arrive by Wednesday just so I have it if needed.

Thanks, 68fb, for that explanation, I have more of a targeted location on the board to deal with tomorrow.
 

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Discussion Starter #11
I was able to borrow my neighbor's fluke (electrician) and found a dead solenoid.

From the photo, you can see, the twistie tie had a piece, that, when the cover was installed, pushed the pcb down a bit, breaking the solder on the right two pins.

All other solenoids register 3.6-3.7 resistance except this one.

I'm going to hit up my local radio shack for one of those solder sucker things and re-solder this joint today and re-test.

I'm still boggled how the vanos tests passed with this thing completely disco.

Also, I am NOT moving or bending this pcb, I know those solenoid poles are a weak point and resistance from the inner pin (solenoid) is 3.6.

No other wires have been pinched/spliced in any way, but for those that have the twistie tie, I would clean up the end so this doesn't happen to anyone else.
 

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The solenoid with the broken solder in the pic is the outlet solenoid for the intake cam. But you also had a code for the inlet solenoid for the intake cam, which is the one above the one in the pic.

You need to check the soldered joints for that one too. Do a wiggle test on all the wires and soldered connections while reading resistance. Read the resistance across the pins in the connector so you test all connections and wiring. Since the DIS test passed, I suspect an intermittent fault.

Especially wiggle the little PCB mounted on the solenoid as it has been known for a solenoid pin to break down inside the epoxy where it is very hard to see.

Malcolm
 

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Discussion Starter #13
100% success. I re-soldered the rest of them and had my wife wiggle the solenoids gently while I checked for resistance. They all work, sound the same pitch and the car fired up perfectly, no codes returned.

I'll take the car out to operating temperature as soon as the rain subsides a bit.

Thanks again to this board. Aside from having to pick up some solder, $7.99 beats 2 large any day of the week!
 
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