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Air and Fuel› Superchargers, Turbochargers and Components
Forge
Bypass Valve Polished
SKU: FMDVCS14A
Easy — 1–2 hours
Overview
This valve offers greater longevity compared to OEM diaphragm valves and can be fitted with different springs to accommodate increased boost pressure or engine modifications. It is recommended to service the valve every 3 years or 20,000 miles. The box includes the FMDVCS14A valve, an uprated yellow spring, and a Forge sticker.
Show original supplier description
Vehicle Symptoms
- Boost pressure spikes under hard acceleration
- Fluttering or whooshing sound from engine bay
- Loss of power during high RPM
- Check engine light with boost-related codes
- Erratic idle when engine is cold
Diagnostic Codes
- P0234 – Engine Overboost Condition
- P0243 – Turbocharger Wastegate Solenoid A Malfunction
- P0244 – Turbocharger Wastegate Solenoid A Range/Performance
- P0236 – Turbocharger/Supercharger Boost Sensor A Range/Performance
- P0299 – Turbocharger/Supercharger Underboost
Relevant Conversations
- P0234 code after tune fix
- Forge bypass valve vs OEM diaphragm
- Fluttering noise on boost 2.0T
- Best piston bypass valve for Audi S3
- Boost cut under load solution
- FMDVCS14A install guide
- Random misfire after boost spike
- Replace diverter valve with Forge
- Bypass valve failure symptoms
- DIY boost leak test with smoke machine
Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
Fitment
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Specifications
| Brand | Forge |
| Part Number | FMDVCS14A |
| Category | Air and Fuel |
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