[Gabe]

For quick context: Car has been in and out of multiple different mechanics trying to fix a constant Drivetrain Malfunction pop-up, which has been on and off for the past maybe 4 months, and every time after it has been ‘fixed’ it comes back. Last time, solenoid in VANOS replaced.

And now, with this most recent visit, technician says he has to dig for more than 6 hours on the engine($1k+) to figure out whether the engine is skipping time, which he says he has seen sometimes w these BMWs. Multiple times I was given clarity to the possibility of needing to replace engine once tech has figured out whether it’s actually time skipping or not.

Any ideas on the natural process for a BMW when it has this type of problem, relating to VANOS, Timing, and drivetrain malf.? Should I expect to be ready to have to sell her to a junkyard soon?
Any info is appreciated!

[CoffeeBean]

Very well known problem of the timing chain stretching on the N20/N26 engine prior to early 2015. Does it make a whining noise when revving? Is there excessive rattling at idle? If you take the oil fill cap off can you move the timing chain at all with your finger? (with the engine off!!)

SIB:https://static.nhtsa.gov/odi/tsbs/20...04534-9999.pdf

[StradaRedlands]

CoffeeBean has your answer... get it to someone that has done the guide replacement previously. Preferably several of them. Are you taking it to the dealer or a BMW/Euro specialist? This is a VERY well known problem, so I think you really need to question the shop you've taken it to :-/

It's going to be expensive, but if the mechanic knows what they're doing, it's a straightforward fix. You'll have to decide if it's worth it based on miles/condition/local market conditions.