logo

BMW 840Ci Fuel Injector Replacement at your home or office.

Our mobile mechanics offer services 7 days a week. Upfront and transparent pricing.

Estimate price near me

Service Location

Customer Ratings

(13)

Included for free with this service

Online Booking

Mechanic comes to you

12-month / 12k-mile warranty

Free 50 point safety inspection

Our certified mobile mechanics can come to your home or office 7 days a week between 7 AM and 9 PM.

See availability

Customer Ratings

(13)

Fuel Injector Replacement Service

How much does a Fuel Injector Replacement cost?

On average, the cost for a BMW 840Ci Fuel Injector Replacement is $697 with $529 for parts and $168 for labor. Prices may vary depending on your location.

CarServiceEstimateShop/Dealer Price
1995 BMW 840CiV8-4.0LService typeFuel Injector ReplacementEstimate$1710.60Shop/Dealer Price$2073.35 - $3133.25
1996 BMW 840CiV8-4.4LService typeFuel Injector ReplacementEstimate$1233.69Shop/Dealer Price$1502.16 - $2298.93
1997 BMW 840CiV8-4.4LService typeFuel Injector ReplacementEstimate$1233.69Shop/Dealer Price$1502.22 - $2299.02
1994 BMW 840CiV8-4.0LService typeFuel Injector ReplacementEstimate$1692.58Shop/Dealer Price$2049.23 - $3104.56
Show example BMW 840Ci Fuel Injector Replacement prices

What is a fuel injector and how does it work?

A fuel injector is a fuel metering device that sprays atomized droplets of fuel in a specific pattern into the engine’s intake manifold or directly into the combustion chamber. The injector has a solenoid and valve within and the operation, or pulsing, of the solenoid is controlled by the powertrain control module (PCM). The PCM controls the solenoid’s “on” time in order to keep the air-fuel ratio optimized while the engine load and operating conditions constantly change. Fuel injectors are usually connected to a fuel rail located on the top of the engine and the fuel rail, in turn, is supplied with fuel under pressure from the fuel pump located in the fuel tank.

When to consider replacing a fuel injector:

  • Rough idle, loss of power, or misfiring. Poor engine operation has many causes but faults in the fuel injection system, including the fuel injectors, are high on the list of possibilities.
  • Odor of raw gas or visible leaks. Fuel injectors should not leak fuel into the intake manifold when the car is off. If you notice any fuel odor around your car, the possibility of a leaking fuel injector should be considered. There should be no external leak from a fuel injector. If an externally-leaking injector is suspected, do not start your car due to the fire hazard.
  • Check engine light. Some fuel injection failures, for example, a faulty solenoid, may cause a trouble code to be set in the PCM and that will cause the check engine light to illuminate. The codes are read and the fuel injector is tested directly, as needed.
  • Major engine repairs, engine replacement, or lengthy storage. All fuel injectors will have deposits given enough mileage. These deposits can cause an imbalance in the performance of the injectors from cylinder to cylinder. When an engine is already disassembled, or if you are installing a new engine, that is a perfect time to service the injectors as a set. All injectors have tiny internal filter baskets. A professional injector service facility will clean each injector ultrasonically and replace these filters for a relatively low cost.

How do mechanics replace a fuel injector?

Injectors can be serviced once removed from the car or replaced outright with new injectors. If the injectors are serviced, specialized cleaning and test equipment are required. The choice to repair versus replace will depend on exactly what is wrong with the injector as well as customer preference. Either option requires removing the injector from the car and the following procedure is typical:

  • Once the engine is cold, the pressure within the fuel rail is relieved by briefly running the engine with the fuel pump fuse out.
  • The upper plenum on the intake manifold is removed along with any cables, hoses, or wiring that restricts access.
  • The supply and return lines are removed from the fuel rail. The electrical connectors to each fuel injector are unlocked and removed. The fuel rail is then unbolted and removed from the intake manifold.
  • The injector(s) requiring replacement are removed from the fuel rail, taking care to not allow any debris to enter the exposed openings. An O-ring seal usually holds the injector very firmly in a finely polished bore in the fuel rail.
  • Using a new O-ring, the serviced or replaced injector is re-inserted into the fuel rail — using engine oil on the O-ring to prevent damaging it. O-rings in this application fit very tight to prevent fuel leaks.
  • The fuel rail is re-installed and the supply and return lines are re-connected. The plenum is re-installed along with all cables, hoses, or wiring.
  • Finally, the engine is run, there is a careful check for leaks, and the vehicle is road tested.

Is it safe to drive with a fuel injector problem?

Yes, so long as there is no external leak of fuel from a broken or malfunctioning injector, it is safe to drive the car. However, if the injector is known to be malfunctioning, it can cause engine misfires, excessive emissions or, in the case of a badly leaking injector, can overload and overheat the catalytic converter. Additionally, fuel efficiency will always be diminished if the fuel injectors are not working properly.

When replacing a fuel injector keep in mind:

  • Using high quality (Tier One) gasoline may reduce deposits on fuel injectors and prolong their life.
  • If an injector problem develops that requires removal of one injector, the best practice is to remove and service all of the injectors at the same time. That service might involve replacement of the electrically failed injector along with off-the-car cleaning of the remaining injectors. Serving all injectors at once ensures the injector set will be balanced, in terms of flow rates, and in turn promote smooth operation of the engine.
  • Do not use fuel system cleaning compounds, or procedures, unless such materials are specified by the manufacturer of your car.
  • On the car cleaning of fuel injectors is not as effective as off-the-car cleaning because injectors have tiny internal filter baskets that should be replaced as part of the process of servicing a fuel injector.

Fast and easy service at your home or office

Backed by 12-month, 12.000-mile guarantee

Number of BMW Fuel Injector Replacement services completed
143+
services done by our mechanics
TOTAL NUMBER OF EXPERT BMW MECHANICS
1200+
experts on our platform
Yourmechanic was featured in

New York Times NBC CBS Forbes INC Tech Crunch

Learn more about us

Meet some of our expert BMW mechanics

Real customer reviews from BMW owners like you.

Excellent Rating

(13)
Rating Summary
12
1
0
0
0
12
1
0
0
0

Jeremy

21 years of experience
802 reviews
Request Jeremy
Jeremy
21 years of experience
Request Jeremy
by Thomas
BMW 840Ci V8-4.4L - Battery - Boynton Beach, Florida
On time, nice guy, always does a good job. I will be in touch with him and YourMechanic.com again in the near future. Thanks again!

Adam

18 years of experience
263 reviews
Request Adam
Adam
18 years of experience
Request Adam
by Thomas
BMW 840Ci V8-4.4L - Car is not starting - Boynton Beach, Florida
Adam was great. He was on-time and had to wait because of a stupid HOA rule. He got the car started again recommended a good charger, and was extremely through in his inspection that identified a couple problem with the oil caps that need to be replaced. I highly recommend Adam and plan n using him again when i receive the quote for the recommended services.

Pierre

10 years of experience
366 reviews
Request Pierre
Pierre
10 years of experience
Request Pierre
by Raynel
BMW 328i xDrive L6-3.0L - Fuel Injector - Somerville, Massachusetts
Great guy over all came on time very professional.

Fred

18 years of experience
389 reviews
Request Fred
Fred
18 years of experience
Request Fred
by c
BMW 328i L6-3.0L - Fuel Injector - Houston, Texas
I needed my fuel injector to be replaced. Fred was very knowledgeable and fast with repairs. I would definitely recommend him for repair services. Thanks, again!

Excellent Rating

(13)
Rating Summary
12
1
0
0
0
12
1
0
0
0
Number of BMW Fuel Injector Replacement services completed
143+
services done by our mechanics
TOTAL NUMBER OF EXPERT BMW MECHANICS
1200+
experts on our platform
Yourmechanic was featured in

New York Times NBC CBS Forbes INC Tech Crunch

Learn more about us

Recent articles & questions

P3478 OBD-11 Trouble Code: Cylinder 10 Exhaust Valve Control Performance
What What the P3478 code means When starting your vehicle, and when the vehicle is operating under a heavy weight, the engine will work in V8 mode. But when driving conditions are light, the engine will disable 4 of the...
Read more
How Long Does a Timing Cover Last?
A A timing cover protects parts such as the timing belt, timing chain, and gears inside of your vehicle. They are made from either plastic, metal, or a combination of synthetic materials. In modern vehicles, the covers are designed to...
Read more
P0154 OBD-II Trouble Code: O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 1)
P0154 trouble code definition 02 Sensor Circuit No Activity Detected (Bank 2 Sensor 1) What the P0154 code means The oxygen sensor’s...
Read more

Shifting problems at high speed

My guess is that the overdrive relay or solenoid has failed. If either of these parts fail, your Volvo will not shift into overdrive. This is a very common problem on Volvos such as yours. A trained professional, such as...
Read more

Rough idling and lacking horse power - 1982 Mercedes Benz 380SL

Hello. There could be a problem with the coolant temperature sensor (https://www.yourmechanic.com/services/coolant-temperature-switch-sensor-replacement). I would also suspect that there could be a problem with the ignition control unit. The fuel pump (https://www.yourmechanic.com/services/fuel-pump-replacement) could also be contributing to the problem you are...
Read more

I changed my oil pump and now when I try to start it it only clicks once

Unfortunately you have already damaged the motor running the engine until it dies when it lost oil pressure. The bearings for the crankshaft (https://www.yourmechanic.com/services/crankshaft-position-sensor-replacement) and camshaft (https://www.yourmechanic.com/services/camshaft-position-sensor-replacement) have been starved of oil and seized the engine. You will need to...
Read more
  1. Home
  2. Estimates
  3. BMW
  4. 840Ci
  5. Fuel Injector Replacement

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (844) 997-3624 · hi@yourmechanic.com

Read FAQ
GET A QUOTE