Why does my Toyota Prius V run rough or misfire?

Short answer: A Prius V that runs rough or misfires with a check engine light often has carbon-clogged EGR ports in the intake manifold. Owners recommend cleaning the manifold, ports, EGR valve and cooler. Rear brake moaning in cold weather is a known noise.

Symptom: The engine shakes, the check engine light comes on with a misfire code, or the rear brakes moan in the cold.

What to check first

1. Read the codes, especially misfire codes.
2. Ask the dealer whether the Toyota bulletin for 2ZR-FXE EGR clogging applies.
3. Have the intake manifold ports, EGR valve and cooler inspected.
4. For brake moaning, have the rear brakes inspected.

Likely causes

1. Clogged EGR ports in the intake manifold. EGR (exhaust gas recirculation) sends some exhaust back into the engine. On this engine each cylinder has a small port that can clog with carbon, leaving that cylinder running differently and causing a misfire.
2. EGR valve and cooler carbon. Carbon also builds up in the EGR valve and cooler.
3. Rear brake noise in the cold. Some Prius V owners hear moaning from the rear brakes in cold weather.

What it usually costs

Owners didn't post prices. EGR cleaning means removing the intake manifold; get a quote.

Is it safe to keep driving?

A misfire can damage the catalytic converter over time. Get it fixed soon. Brake moaning alone isn't usually dangerous.

DIY or shop?

EGR cleaning is an advanced DIY job. Many owners use a shop.

Recalls, bulletins and complaints in plain words

• Related recalls: NHTSA lists hybrid inverter recalls for the Prius V that can also cause power loss: 15V449000 (some 2012-2014 Prius V, an inverter part can overheat and cut power, and the hybrid system may shut down), 18V684000 (2012-2014) and 20V369000 (2014-2017 Prius V not covered by 18V684, excessive voltage in the inverter's power module can shut the hybrid system down and stall the car). These aren't about EGR clogging, but rule them out first. 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 complaints: 221 keyword-matched complaints for Toyota Prius V 2012–2017 (of 1744 unique complaints queried, NHTSA complaints API by model year, queried 2026-10-28; keywords: egr, misfire, shake, knock, head gasket, coolant, noise, moan). This counts complaints that mention these words. It is not a defect finding.

What owners report

• In Public service announcement - 3rd generation Prius V 2011-2016 owners EGR clogging issue on Car Talk, an owner warned that the EGR ports in the intake manifold on these engines clog with carbon and recommended cleaning them. A member cited a Toyota service bulletin covering some 2012-2015 Prius V with the 2ZR-FXE engine that run rough or set a check engine light.
• In Prius v 2012 "moaning" noise on Car Talk, a 2012 Prius V owner heard moaning from the rear brakes in cold weather. Members said Toyota was aware of the noise.

Quick tip

If your Prius V has high miles and a misfire, ask about EGR clogging first.

Vehicle focus: Toyota Prius V, 2012-2017.

Safety / mechanic note

Misfires and brakes need inspection. Verify with a mechanic.