P0029
Exhaust Valve Control Solenoid Circuit Range/Performance Bank 2P0029 is a generic OBD-II powertrain diagnostic trouble code: Exhaust Valve Control Solenoid Circuit Range/Performance Bank 2. It is logged by the engine control unit when the powertrain monitor detects that a specific fault threshold has been exceeded — typically resulting in the malfunction-indicator lamp (MIL / check-engine light) being illuminated.
What P0029 means
P0029 is stored when the PCM determines that the exhaust valve control solenoid circuit on Bank 2 is outside its calibrated operating range or not performing as commanded. Bank 2 is the engine bank that does not contain cylinder #1; this code therefore applies only to V-type and flat (boxer) engines. The fault is a counterpart to P0027 (same fault, Bank 1) and belongs to the Variable Valve Timing (VVT) / Variable Camshaft System (VCS) group of powertrain codes.
The PCM sets P0029 when it detects a voltage deviation of approximately 10% or more from the expected reference voltage at the Bank 2 exhaust camshaft actuator solenoid, or when actual exhaust camshaft phase on Bank 2 fails to reach the commanded target. Because the actuator is purely hydraulically driven via engine oil, oil level, pressure, and quality are the dominant fault triggers — well ahead of solenoid or wiring failures. With the fault present, Bank 2 exhaust valve timing is fixed, degrading scavenging efficiency, increasing exhaust emissions, and reducing power particularly at mid-to-high RPM. An audible ticking from the Bank 2 exhaust-side actuator area is sometimes noted during warm-up or hard acceleration.
Common causes
Most-frequently reported root causes when P0029 is logged.
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1
Low engine oil level — the most common cause; the exhaust VVT actuator on Bank 2 requires adequate oil volume and pressure to operate
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2
Low oil pressure from a worn pump, collapsed pickup tube, or excessive bearing clearance
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3
Incorrect engine oil type or grade (too thin or too thick for the application)
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4
Faulty exhaust valve control solenoid on Bank 2 — degraded coil windings, mechanical binding, or stuck-open/closed valve
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5
Open or short circuit in the Bank 2 exhaust solenoid wiring or corroded connector pins
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6
Carbon deposits or sludge blocking VVT oil galleries or the actuator vane passages
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7
PCM software calibration mismatch after an incomplete or incorrect reflash (rare)
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8
Failed PCM — internal driver circuit for the solenoid output (uncommon)
Symptoms drivers notice
How to diagnose P0029
A typical diagnostic flow when this code is present.
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1
Check engine oil level and quality; top up or change to the correct specification, clear the fault, and road-test — this resolves many cases
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2
Conduct an oil pressure test with a mechanical gauge at idle and 2,000 RPM; values below OEM minimums indicate a pump or internal engine issue requiring further investigation
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3
Inspect the wiring harness and connector at the Bank 2 exhaust solenoid for chafing, corrosion, bent pins, or water intrusion; verify reference voltage and ground continuity with a DVOM
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4
Measure solenoid coil resistance (unplug connector; typical range 6–15 Ω depending on OEM); replace solenoid if resistance is open or shorted
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5
Use a scan tool to command the solenoid and observe live exhaust camshaft phase data; if the cam does not respond despite a good electrical circuit, suspect blocked oil passages or a seized actuator vane
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6
Remove and clean the solenoid filter screen; perform an engine oil flush if heavy sludge is found, then retest
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7
Check for related codes such as P0019 (Camshaft Position Correlation, Bank 2) that may indicate a timing chain or actuator mechanical fault; diagnose companion codes first
Related powertrain codes
Frequently asked questions
Can P0029 cause the car to fail an emissions test?
Yes. Stuck exhaust valve timing on Bank 2 prevents optimal combustion and exhaust scavenging, raising HC and NOx emissions. Many vehicles with active P0029 will fail a tailpipe sniff or OBD-II readiness test.
Is P0029 serious enough to stop driving?
Not immediately — the vehicle typically remains driveable. However, if low oil pressure is the cause, continuing to drive risks serious engine damage. Confirm oil level and pressure before treating it as a minor inconvenience.
How do I distinguish a bad solenoid from a clogged oil passage?
Electrical testing (resistance and voltage checks) will rule out the solenoid. If the circuit tests good but the cam does not respond to commanded changes via scan tool live data, the fault is mechanical — a blocked passage or seized actuator vane.
What is the typical repair cost for P0029?
Oil change to correct spec: $50–$100. Solenoid replacement: $150–$400 parts and labour depending on accessibility. Actuator replacement or oil passage cleaning: $400–$800+. PCM reflash: $100–$200 at a dealer.
Disabling P0029 in software
RaceTune can permanently disable P0029 — and any other OBD-II diagnostic trouble code — on every ECU family we support. The monitor is disabled inside the ECU itself, so the fault stops being logged: the warning light stays off and the engine never enters limp mode for this code. The change is tied to your exact software version.
Software modifications affect emissions compliance and are not road-legal in many jurisdictions. RaceTune service files are intended for motorsport, off-road, and export use.
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