BMW 135i: Common Problems & Reliability Guide
Also covers: 335i, 535i, 640i, X6
Real, sourced data · last reviewed 2026-07-31
VANOS Solenoid Clogging / Gear Assembly Failure
Engine / Valvetrain · severity: Low-Medium for the common solenoid-clogging tier; High for the rarer TSB-documented gear-assembly failure, especially if attaching bolts have sheared · confidence: 78/100 · 3 cited sources
What to check before you buy
- Scan for the codes above - a rattling noise, loss of power, and Service Engine Soon light are the TSB's own stated symptoms
- Rule out the cheap, common cause (solenoid screen clogging/varnish) before assuming the expensive one - the same fault codes fire for both
- If solenoids are clean, inspect the VANOS gear assembly and its attaching bolts per BMW TSB SI B12 14 12
- If bolts are found broken, every fragment must be located and retrieved before final repair - do not skip this
Full repair-cost estimate, TSB/recall reference and the specific buyer negotiation tip for this issue are included in the R99 vehicle report.
This guide summarises documented, sourced findings for the BMW 135i generally. It is not an assessment of any specific vehicle - mileage, service history and condition vary by example. A full AutoLytiQs report checks a specific listing against this data plus a live South African market valuation.