Why won't my Scion xD start after sitting, or why does it shut off at stops?

Short answer: If your xD cranks but won't start after sitting a day or two, then finally starts with a cloud of smoke and a strong gas smell, members suspected a leaking fuel injector flooding a cylinder, or a fuel pump that can't hold pressure overnight. If it shuts off while idling at stops, get the actual trouble codes and have idle speed checked. A check engine light doesn't mean the engine is finished.

Symptom: After sitting, the engine turns over but won't catch. After several tries it starts, puffs smoke and smells strongly of gas, then runs fine. Or it stalls at stops while idling, sometimes with the check engine light on.

What to check first

1. Have fuel pressure checked while running and after shutdown. It should hold pressure for hours.
2. If it's hard to start, hold the gas pedal to the floor while cranking. That tells the computer to cut fuel and helps clear a flooded engine.
3. Get the trouble codes read (many parts stores do it free) and write down the code numbers.
4. Ask the shop to check idle speed. Low idle points to the electronic throttle body (the motor-driven valve that controls airflow).
5. Check the oil level and how much it uses, since high mileage xDs can burn oil.

Likely causes

1. Leaking fuel injector. Floods a cylinder while parked, causing smoke and a gas smell on startup.
2. Weak fuel pump or check valve. A member's guess on a high-mileage car; pressure that bleeds off overnight is the clue.
3. Dirty or faulty electronic throttle body. Suggested for stalling at idle if idle speed is out of spec.

What it usually costs

A member estimated about $125 for a shop diagnostic. No owner posted repair prices.

Is it safe to keep driving?

Stalling at stops can leave you stranded in traffic, and a raw-fuel smell is a fire risk. Get it diagnosed soon. Verify with a mechanic.

DIY or shop?

DIY for code reads, throttle body cleaning and the floored-pedal start. Fuel pressure tests and injector work are best done by a shop.

Recalls, bulletins and complaints in plain words

• Recalls: NHTSA lists no recall for stalling or the fuel system on the Scion xD in the model years we could check on 2026-10-26 (the recall lookup returned an error for 3 model-year queries). Check your VIN at nhtsa.gov/recalls. If your car is part of a recall, the dealer fixes it for free.
• NHTSA complaints: 7 keyword-matched complaints for Scion xD 2008–2014 (of 37 unique complaints queried, NHTSA complaints API by model year, queried 2026-10-26; keywords: stall, dies, idle, won't start, crank, fuel pump, injector, throttle) (NHTSA returned no complaint data for 2 model-year queries). This counts complaints that mention these words. It is not a defect finding.

What owners report

• In 2008 Scion xD won't start on Car Talk, a 2008 xD with 230,000 miles turned over but wouldn't start after sitting two days, even with a jump. It finally started with a cloud of smoke and a strong smell of gas, the second time it happened. One member said it sounded like a leaky injector flooding a cylinder and suggested holding the pedal to the floor while cranking; another guessed a failing fuel pump and said to check whether pressure holds overnight.
• In 2008 Scion xD turns off while idling on Car Talk, an owner said their xD had started shutting off while idling at stops, and their mechanic told them it may be the engine and not worth fixing once the check engine light came on. Members disagreed: they said a check engine light just means there's a problem, to pay for a proper diagnosis (about $125), and to have idle rpm checked because a faulty electronic throttle could cause it.

Quick tip

A check engine light is a starting point, not a death sentence. Get the code numbers in writing before anyone tells you the car isn't worth fixing.

Vehicle focus: 2008–2014 Scion xD (1.8L four).

Safety / mechanic note

If you smell raw fuel, don't keep cranking or driving. Have it checked first. Verify with a mechanic.