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I'm having an issue with my vanos system. I'm getting a rough idle and codes 283D, 287D and 2845.
When I reset the vanos adaptations, the intake values are bang in the middle: 149.8, when it should be 140 to 160. However, the exhaust value is 60.2, when it should be 40 to 60.
Does anyone know what these values actually mean? Are readings taken from the camshaft position sensors, which have 3 wires or the vanos solenoids themselves, which only have 2 wires? I've swapped the intake and exhaust solenoids over and the fault doesn't transfer.
The timing is spot on. I set it using a high quality locking tool.
Thank you, the faults all refer to the actuator movement, on intake, and exhaust. If you are certain the mechanical timing is correct, then I would assume the actuators are seized/faulty and I would replace them and retest.
Ah, yes. That's a good idea. Thank you.
The truth is, I already replaced both solenoids and the fault is still there. I'm not proud of myself.
I was hoping to prove the fault now, rather than to replace any more parts needlessly. I know that this could be a mechanical fault and that there is little electrical feedback from the system, other than the camshaft position sensors.
Can you explain what takes place during this resetting of vanos adaptations process and what the adaptation values mean? I've been plugging away at this fault for 4 months now and absolutely nobody can say what is actually going on.
Probably only the Mini/BMW engineers know but I'm sure they'll not be willing to share their knowledge.
The Vanos solenoids are powered by the DME, the DME will change voltage, and polarity depending if the engine timing is to be advanced or retarded, I attached a technical explanation on how the system works.
Thank you. That's a great explanation.
I suppose there is no way to tell exactly what signal the DME should sending to the vanos solenoids under any given condition.
I think I'll just need to replace the vanos units (phasers), even though I don't know if they're faulty. They're £105 each though. I've exhausted every other avenue.
Thank you again for your help.
Ok,, since you have already replaced the Vanos solenoids, I would double check the mechanical timing, see attachment for procedure. make sure the crankshaft is locked. and the timing chain has the correct pre-tension on it since no oil pressure is putting tension on the chain itself.
Also. I would check for a stretched timing chain. I also attached the procedure to check for the stretched chain.
Edit... see attachment for timing, it states when crank shaft is locked with special tool to put a wrench/spanner on the camshaft and attempt to move it, if the camshaft moves, the phaser itself is faulty and will need to be replaced.
You may have to purchase special tools to do this properly. but it would be the next step.
Again, thank you so much for taking the time to help. I really appreciate it.
I replaced the chain about 1000 miles ago with a good quality item, also the guides, lower sprocket, tensioner and stretch bolts (all torqued correctly).
I have also replaced the o rings on the exhaust camshaft which control the oil pressure to the vanos unit.
I checked the timing just last week and it's bang on. I've learned how to do this properly through many attempts and my Laser tool cost £150 so I know it's a good, accurate one.
Both vanos units are locked when I try to rotate them. I've had them both off in a vice too and they're both locked by the internal pin due to there being no oil pressure applied. I THINK this is how they should be.
The only fault I can think of that remains is that the vanos units, or at least the exhaust one, is not rotating correctly when oil is sent to it from the exhaust vanos solenoid, however there appears to be no method of checking or confirming this.
I'm reluctant to just replace the unit without knowing that it's broken.
I have heard that a software update has fixed this issue for some people, however I don't understand how this fault would suddenly, appear like it has if software is the issue.
I found no TSB for SW updates for this problem, there are SW updates to fix vanos issues but not for your engine, and fault codes.
I did find a TSB for the chain tensioner being faulty. I attached the TSB please read and see if it applies.
edit...sorry, you have a N12 engine, this TSB applies to N14 engines. however they may be very similar, I would still check and compare...
edit again, sorry, last time. I compared and yes, the N12, and N14 use the same chain tensioner, so this bulletin should apply to your engine. note. updated part # for tensioner is 11 31 7 607 551.
I have the latest part number tensioner and my measurement is well below the 68mm so I know the chain or tensioner are good.
Yes, the N12 and N14 are identical in terms of timing chain setup. Thank you again, and welcome to my saga.
I was hoping that I could measure the output of the exhaust camshaft position sensor somehow, in order to check the operation of the vanos unit. I'm thinking that's not possible now given the multitude of signals the ECU can send to the vanos solenoid.
Last edit: 4 years 1 month ago by Gerard778. Reason: Typo and extra info
I understand. However, I can not find any specs on what exactly they should be, many times with situations like this one must find, and test on a known good vehicle to get correct readings.
only the engineers know these readings, and most likely they didnt think those values are important to fixing the vanos.
note. it does say the scan tool ( ista ) would run a test plan for this fault code and run you through and it will tell you what readings are correct and not. but it will only tell you in the test plan, which has to have the faulty vehicle for it to run.
