BMW 2A87 means the exhaust cam was late or failed to reach its VANOS target. On applicable E9x N51/N52 328i vehicles, BMW's SIB directs technicians through oil-supply and ISTA test-plan checks rather than immediate parts replacement. Verify oil/filter/pressure, compare exhaust target with actual angle, test the correct solenoid and circuit, and inspect oil passages, adjuster and hook-ring seals only when evidence supports them.
Match the symptom
Select the closest observation. The result changes the first test; it does not name a part to replace.
Check oil supply and correlation promptly.
What can set 2A87—and how to separate it
The order below is evidence-driven, not a universal probability ranking. Vehicle year, repair history, companion codes and the operating condition in freeze frame change where diagnosis should begin.
| Possible cause | Evidence that supports it | First useful test |
|---|---|---|
| Low, wrong or degraded engine oil | Level/specification and CVVT response are abnormal | Oil and filter audit |
| Affected cam oil-control valve or circuit | Command/current or loaded circuit fails | GDS/KDS actuation and circuit test |
| Restricted oil passage or sticking CVVT phaser | Safe pressure but commanded response fails | Hydraulic response test |
| Timing chain, tensioner or cam indexing fault | Stable phase offset, noise or mechanical evidence | Cam/crank waveform and timing inspection |
| Cam sensor/reluctor or ECM-input problem | Dropout, noise or companion circuit code | Signal and correlation test |
Compare exhaust target and actual
Capture the failure at operating temperature and note whether actual angle is slow, fixed or unstable.
Compare intake only under equal conditions; it provides context but does not prove the exhaust component.
Test electrical and hydraulic control
Load-test solenoid control and connector tension and use ISTA activation while watching cam movement.
Verify oil supply first. Debris in the solenoid can be evidence of a larger lubrication or wear problem.
Inspect mechanical items only when directed
Complete the BMW test plan for oil passages, adjuster and hook-ring seals rather than replacing both solenoids indiscriminately.
Confirm repeated hot operation without 2A87 or power reduction.
Save these scan-data clues
Freeze frame is a snapshot of conditions when the PCM matured the fault. It can distinguish an idle-only problem from a load, cold-start or monitor-completion problem. Clearing first throws that context away.
- Exact VIN, platform, model year and engine sales code
- All confirmed, pending and permanent companion codes
- RPM, load, coolant temperature and vehicle speed
- Relevant commanded and actual scan data
- Recent service, repairs and symptom conditions
- Manufacturer bulletin and current software/VIN status
A practical diagnostic workflow
- 01Identify engine and intake/exhaust cam
Engine families and CVVT coverage differ.
- 02Save desired/actual angles and companions
Record temperature, rpm, load and oil history.
- 03Verify oil, filter and mechanical pressure
Do not command CVVT with unsafe lubrication.
- 04Test the correct oil-control valve and circuit
Separate electrical command from hydraulic movement.
- 05Scope cam against crank
Distinguish dropout from a stable phase error.
- 06Inspect phaser and timing only as evidence directs
Avoid sensor or chain replacement by guess.
- 07Perform applicable learning and verify
Confirm commanded tracking and no pending code.
Do not replace the most commonly named component from 2A87 alone. Confirm the exact engine, preserve evidence and complete the manufacturer test sequence before ordering parts.
Why the model year changes the test
The 328i badge covers very different powertrains. North American E9x cars generally use naturally aspirated N51/N52 six-cylinder engines, while F30/F31 cars use turbocharged N20/N26 four-cylinder engines; other markets and swaps vary. Read VIN, chassis, engine designation, DME identification and the complete BMW fault text before using any test. A four-digit BMW fault is not safely interchangeable with a generic P-code or a fault from a 335i.
- 2A87 names exhaust VANOS; 2A82 names intake VANOS.
- E9x N51/N52 and F30 N20/N26 systems use different fault maps and hardware.
- A companion 3100 on an N54 is consequential, but a stock 328i is not N54.
- Hot-only power reduction should be reproduced with data, not repeated hard driving.
2A87 FAQ
Does the code prove the oil-control valve failed?+
No. Oil supply, wiring, passages, phaser, chain and feedback faults can produce it.
Can low oil cause it?+
Yes. CVVT depends on controlled engine-oil flow.
Can I drive?+
Limit driving and stop for rattle, oil warning, stalling or severe running problems.
Should I replace cam sensors?+
Not without waveform or circuit evidence.
Why check P0017?+
It can show that the exhaust cam is no longer correctly correlated with the crankshaft.
Does it prove the chain stretched?+
No. A stable measured offset and mechanical checks must support that conclusion.
Can cleaning the solenoid fix it?+
Only when contamination is confirmed and the approved service method permits it; the oil-system cause still matters.
What confirms repair?+
Desired and actual cam timing track correctly with no pending DTC.
Ford diagnostic references
These documents explain Ford monitor operation. Exact pinpoint tests, connector views and specifications must be selected for the truck's VIN and model year in current service information.
01BMW SIB 11 02 08 — 2A82/2A87 VANOS faultsIncludes specified E90–E93 N51/N52K applications and describes late cam response, oil supply and VANOS test-plan branches↗02BMW Technical Information SystemOfficial VIN-, engine- and ISTA test-plan information↗03BMW owner's manualsOfficial VIN/model operating, warning and maintenance information↗