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Fuel Injector Replacement

What is a fuel injector?

Fuel injectors regulate the amount of pressurized fuel used for each engine cycle. There is one injector per cylinder in an engine.

How does the fuel injector work?

Each time an intake stroke occurs in the engine, the vehicle's computer will send a signal to the fuel injectors, requesting they spray fuel. For heavy acceleration, the duration of the fuel spraying will be longer than if the engine were idling.

Failing fuel injectors can cause engine misfiring and hesitation. The Check Engine Light may come on and set diagnostic trouble code(s).

What are the symptoms related to a bad fuel injector?

When a fuel injector fails or clogs, engine power is reduced and misfires will occur. The check engine light will turn on and, as the issue progresses, the engine may stall immediately after starting, fail to start, hesitate under throttle or vibrate roughly.

Toyota Fuel Injector Replacement Cost Estimates

The average cost for a Fuel Injector Replacement is between $1,883 and $2,308 but can vary from car to car.

Toyota Sienna Fuel Injector Replacement Cost by Year

The average cost for a Toyota Sienna Fuel Injector Replacement is between $1,883 and $2,308 but can vary from car to car.

Disclaimer

Materials Included Under License from Toyota Motor Sales, U.S.A., Inc. License Agreement TMS1008. All information contained in any materials obtained about Toyota, Lexus, and Scion vehicles is based on the latest product information available at the time of publication, is provided “as is” without warranty of any kind, and is intended for service providers and other interested parties in Canada, Mexico, and the United States of America, including Guam, Puerto Rico, and the U.S. Virgin Islands. Specifications and procedures are subject to change without notice. This information is provided expressly for the purpose of use by professional automobile technicians who have special techniques and certifications. Repair or service by non-specialized or uncertified technicians using only this information, or without proper equipment or tools, may cause severe injury to the individual or other individuals and could possibly cause damage to the vehicle. Certain procedures or content elements may make reference to Toyota Warranty policy or practice – these policies or practices are only applicable to Toyota, Lexus, or Scion dealers.

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Fuel Injector Replacement

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What is a fuel injector?

Fuel injectors regulate the amount of pressurized fuel used for each engine cycle. There is one injector per cylinder in an engine.

How does the fuel injector work?

Failing fuel injectors can cause engine misfiring and hesitation. The Check Engine Light may come on and set diagnostic trouble code(s).

What are the symptoms related to a bad fuel injector?

Estimates last updated January 28, 2026

1999 Toyota Sienna Fuel Injector Replacement Cost

The average cost for a 1999 Toyota Sienna Fuel Injector Replacement is between $1,883 and $2,308.

Labor costs are estimated between $317 and $465 while parts are priced between $1,566 and $1,843.
This range does not include taxes and fees, and does not factor in your unique location. Related repairs may also be needed.
For a more accurate estimate based on your location, use our Fair Price Estimator below.

Can I drive with a fuel injector problem?

It's not smart to drive a vehicle with a fuel injector problem. These issues can cause the car to stall every few moments and accelerate unpredictably, creating a hazard. If the problem is bad enough, the vehicle may not even start, making it impossible to drive.

How often do fuel injectors need to be replaced?

On average, fuel injectors tend to fail after 80,000 miles, and require little maintenance. To prolong the life of the fuel injectors, follow the scheduled maintenance schedule for cleaning the fuel delivery system and injectors.

How are fuel injector issues diagnosed?

If fuel delivery system symptoms are present, the technician will first conduct a visual inspection. If the issue isn't clear after a physical inspection, the technician will connect a computerized scanner to the vehicle to read some of its sensors. If there's a fuel injector problem, the technician would most likely find that misfires are happening frequently on one cylinder. The fuel injector or injectors in question must be tested, and may require removal for bench testing. Any failed components must be replaced, and the vehicle will be checked to ensure the problem is fixed.

How is a fuel injector replaced?

Typically, the intake manifold must be removed to access and replace the fuel injectors. This can be a large job that may involve draining the coolant and oil, removing many engine components, and replacing the intake manifold gasket. Some cars, though, are designed with plastic intake manifolds that do not have oil or coolant passages, making this process easier. Once access is available, the fuel injector is disconnected from the fuel rail and electrical connector and removed. The new one is then installed in its place.

Using lower quality gasoline can result in recurring fuel injector problems, even after a fuel injector replacement.

Fuel injector seals should always be replaced along with fuel injectors.

Get a RepairPal Fair Price Estimate® for your 1999 Toyota Sienna.

Our Fair Price Estimate will help you avoid overpaying based on your car, needed service, and labor rates in your area.