What does "Emission system problem" and "Rev Match system problem" mean on my Civic Type R?

Short answer: Both messages come on together because the engine computer found a fault and turned off rev match as a precaution. The stored code tells you which fault. Type R owners traced it to ignition or misfire problems, water after rain, a wiring harness bulletin, and P0607 on an FK8. Get the code read and ask about the harness bulletin before agreeing to a new engine computer.

Symptom: The check engine light comes on with Emission system problem and Rev Match system problem messages. Sometimes the car loses power at high rpm, and sometimes it drives normally.

What to check first

1. Read the stored code.
2. Note whether it happened in rain, at high rpm, or after a fill-up.
3. Ask the dealer to check the wiring harness service bulletin.
4. Have the spark plugs and coils checked.
5. Get a second opinion before replacing the engine computer for P0607.
6. Run your VIN at nhtsa.gov/recalls.

Likely causes

1. Engine misfire or ignition problem. When the engine computer sees a misfire or a fault, it turns on the check engine light and turns off rev match, the feature that blips the throttle for smooth downshifts. Owners mentioned spark plugs and water getting to the ignition.
2. Engine computer fault (P0607). P0607 means the engine computer found an internal problem in its own control module. One FK8 dealer wanted to replace the whole engine computer, while other owners pointed to a wiring harness bulletin first.
3. Wiring harness problem. Owners said there's a service bulletin about a wiring harness on these cars. Ask the dealer to check it before replacing the engine computer.
4. Turbo boost control solenoid, or a one-time fault. One FK8 owner said the same warnings were a turbo solenoid, fixed under warranty. Another owner had the codes cleared and they never returned.

What it usually costs

Owners didn't post prices. A new engine computer is expensive, which is why owners pushed for harness and ignition checks first. Warranty covers newer cars.

Is it safe to keep driving?

If the check engine light is flashing or the car loses power, drive gently and avoid high rpm until it's checked. A steady light with normal driving is less urgent, but still get it scanned soon.

DIY or shop?

Reading codes is DIY. Spark plugs are a moderate DIY. Harness and computer work belong at the dealer.

Recalls, bulletins and complaints in plain words

• Recalls: NHTSA lists 4 recalls for these model years (23V858000, 24V064000, 24V744000, 26V332000). None is about these warnings. Check your VIN at nhtsa.gov/recalls. If your car is part of a recall, the dealer fixes it for free.
• Plain words: The complaint count below shows how often owners reported problems that mention these words to NHTSA. A count is not proof of a defect. NHTSA's model names may group some Type R complaints with other Civic hatchbacks, and some years returned no data.
• NHTSA complaints: 53 keyword-matched complaints for Honda Civic Type R 2017–2025 (of 1148 unique complaints queried, NHTSA complaints API by model year, queried 2026-11-02; keywords: check engine, emission, rev match, limp, loss of power, turbo, boost) (NHTSA returned no data for 4 model-year queries). This counts complaints that mention these words. It is not a defect finding.

What owners report

• In FL5 Emission/Rev Match Check Engine Light on Reddit r/Civic_Type_R, a 2024 FL5 owner with about 5,500 miles was merging in third gear when the car lost all power around 6,000 rpm, jerked forward and threw a check engine light with the warnings. Replies: one owner's car had a mechanic clear the codes and it never came back (maybe bad gas), and an FK8 owner with the same codes said it was the turbo solenoid, fixed under warranty and a bulletin.
• In 18 Ctr Fk8 (emission/rev system problem) on Reddit r/Civic_Type_R, an owner of a stock 2018 FK8 with about 8,000 km got a check engine light after driving in rain and light mud, with the car still running perfectly. The dealer found only P0607 and suggested a new engine computer. Replies suggested checking the engine computer connector, fuse box and grounds for moisture, said a wiring harness bulletin covered some 2017 and 2018 cars (linking a CivicX thread), and one FK8 owner said the same thing turned out to be a misfire from standing water eroding a spark plug after a dealer pressure-washed the engine bay.

Quick tip

Rev match turning off is a side effect. Focus on the code.

Vehicle focus: Honda Civic Type R, FK8 (2017-2021) and FL5 (2023-2025).

Safety / mechanic note

Sudden power loss while merging is dangerous. Verify with a mechanic.