P2A84
- Powertrain
- Manufacturer-specific
- Emissions
Get it looked at now
Driving may cause further damage or leave you stranded. Arrange service promptly rather than waiting.
Alternative Fuel Pump B Compression Stroke Valve Control Circuit Range/Performance
This code is in our catalogue but has not yet been through editorial review, so the guidance below is limited to what our structured data supports. We publish deeper diagnostic content only after a code has been reviewed — here is why.
The control circuit of the compression stroke valve in alternative fuel pump B reports a control circuit range/performance condition. Pump compression stroke cannot be commanded as expected.
A trouble code records what a control module measured. It does not identify which part failed. Test before replacing anything.
- Safe to drive
- Driving may cause further damage or leave you stranded. Arrange service promptly rather than waiting.
- Urgency
- Get it looked at now
- Will it pass emissions
- No
- Check engine light
- Solid
- Hard start, no start, or stalling under load
- Power loss especially at high load or rpm
- Possible long cranking time
Many vehicles show no symptom at all beyond the warning light. The absence of a symptom does not mean the fault is not real.
| # | Cause | How often | Component |
|---|---|---|---|
| 1 | Valve responds slower than expected | Very common | — |
| 2 | High-resistance contact in connector | Common | — |
| 3 | Sensor element aged beyond calibration window | Occasional | — |
Ordering reflects how often each cause is responsible in general, not a probability for your vehicle. Confirm by testing.
- Alt Fuel Pump B Compression Stroke Valve
- Wiring Harness
- AFCM
- Definition
- Generic code set (SAE J2012 / ISO 15031-6) via the OBDexopen database, dedicated to the public domain under CC0-1.0.
- Diagnostic guidance
- Written and reviewed in-house. See our editorial policy.
- Review status
- Awaiting review
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