SPDZ1 AFM & NPP Exhaust Valve Simulators for C8 Corvette (2020-2024)

💡 Say goodbye to check engine lights when upgrading your C8 exhaust.

If you’ve installed an aftermarket cat-back exhaust on your 2020-2024 C8 Corvette that doesn’t include factory-style AFM (Active Fuel Management) or NPP (Dual-Mode Performance) valves, you’ve likely seen the dreaded CEL (Check Engine Light). These plug-and-play AFM/NPP valve simulators are the proven solution.

🔧 How They Work

• Plugs directly into your C8’s factory exhaust valve harness

• ECU is “tricked” into thinking the valves are still present

• No cutting, no splicing — just connect, zip-tie out of the way, and drive

• Prevents AFM/NPP valve malfunction codes and CEL warnings

✅ Why You Need Them

• Aftermarket Exhaust Upgrade: Almost every C8 with an aftermarket exhaust needs AFM simulators.

• Performance Models (NPP): If your C8 came with the factory Valved Performance Exhaust, you’ll also need NPP simulators unless your new exhaust has valves.

• Base Model Exhausts: Only AFM simulators are required.

📦 Fitment Guide

• Base Model Exhaust (Non-Valved): Requires 1 pair (AFM only) to avoid CEL.

• Performance Model Exhaust (Valved/NPP): Requires 2 pairs (AFM + NPP) to avoid CEL.

• This listing is for ONE PAIR.

🔥 Key Benefits

• Eliminates CELs caused by missing AFM/NPP valves

• Seamless integration with factory wiring

• Works with all 2020, 2021, 2022, 2023, and 2024 C8 Corvettes

• Plug-and-play installation (no permanent modifications)

• Built tough for long-lasting reliability

• This purchase includes (1) Pair - (2) Simulators

Upgrade your C8 the right way — enjoy your aftermarket exhaust sound without the hassle of warning lights or error codes.

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