Justsendit 2 Report post Posted August 12, 2019 I have a bmw n46 rb20. Bought for a steal, I thought.. Anywho full rebuild later (minor port and polish) and a decat and I'm getting a code. P1048 valvetronic servo motor voltage. I've replaced the stepper motor. I was going to replace the eccentric shaft sensor but wanted to check there's nothing easier that could cause the issue, I.e a ground or fuse. Any information is appreciated thanks ? Picture of my lady Quote Share this post Link to post Share on other sites
Justsendit 2 Report post Posted August 12, 2019 Also I forgot to mention, I haven't been I to relearn vanos yet, still runs and drives though which I wouldn't have expected with that fault code Quote Share this post Link to post Share on other sites
zero 1162 Report post Posted August 12, 2019 I've rebuilt one of these, but didnt get any codes. Im presuming you used the cam locking tools? And hopefully you didnt polish the inlet side of the head as that will decrease performance. Quote Share this post Link to post Share on other sites
Justsendit 2 Report post Posted August 12, 2019 Not over polished left some roughage for some air turbulence, but upon learning some more post the build I may have over opened ?. Do you think the problem I'm having will be the eccentric shaft sensor? Quote Share this post Link to post Share on other sites
zero 1162 Report post Posted August 12, 2019 To be honest I don't know, but there are some very knowledgeable people on this board who probably will. I didn't encounter any codes when I swapped the head on my n46b20. Was the fault there before you rebuilt the head? What parts did you actually change? I presume valve stem seals/chain/chain guides etc? Also what scanner are you using as the higher spec scanners are alot more accurate and better at isolating faults. Quote Share this post Link to post Share on other sites
Jacko 2158 Report post Posted August 12, 2019 Im not familiar with the N46, but tinkered around a few N52s, step one would be to do the vanos relearn with ista+ and see if that solves it (its one click). If its doing something like hitting the stops before it expects too, the voltage sag when that occurs could throw an error like the above, and wouldnt be a continuously occuring fault. Quote Share this post Link to post Share on other sites