BMW 530d N57 hunting

[sams255]

My car has around 290k miles. And when it is doing a regen it's hunting, what could it be as I have had no errors on Carly.

[Gassmi]

Hunting during regen usually points to a boost or fuel delivery issue rather than anything the ECU flags. Common culprits: sticking EGR valve, a small boost leak (intercooler pipe), or a tired MAP/MAF sensor. At 290k your turbo vanes could also be sooted up and struggling to hold steady boost when the regen raises exhaust temps. Carly won't always catch these because they're mechanical/gradual, not hard faults. Worth checking live boost and EGR readings during a regen to see what's fluctuating.

[Doesitdrive]

Buy a smoke machine from Amazon or Ebay, best tool we bought for a while, finds any leaks on the air side.