Lotus Elan Central
Fuel Injector Removal

Here is an excellent informational write-up by Dave Meyers about fuel injector removal and upgrade. These instructions and the "sweat and tears" advice will be of great benefit should you need to dissect your injectors for Upgrade/Overhaul/Replacement! --Doug


If you choose to change the stock configuration of your Elan, you do so at your own risk! In short, if you damage your Elan or endanger your life as a result of something you read here, it is your responsibility. Please use common sense.

Optional Parts Needed:

  • Larger fuel injectors (If you are ordering through RC Engineering, mention you need their model PL-8 “Bosch-type” low impedance injector. This should get you what you need.)
  • 3-bar MAP sensor, piggyback fuel computer, or other fuel control

Tools Needed:

  • 12mm socket
  • 14mm socket
  • Socket extension
  • Needle-nose pliers
  • Die pick
  • A long, standard screwdriver
  • T-26 Torx bit

NOTE: This procedure explains removal of the fuel injectors with the intake plenum INTACT! The procedure is much simpler with the plenum out of the car.

Before removing any parts, you must relive pressure form the fuel system. While the car is running, pull the fuse for the fuel pump. After it stalls, crank the engine for a few seconds to remove as much remaining fuel from the fuel rail. Then perform the following steps:

  1. Disconnect the battery.
  2. Remove the (2) 12mm bolts holding the black plastic wire cover.
  3. Remove the small wire clips that hold the plastic electrical connectors to the injectors. This is possibly the toughest part of the job. Use the die pick in conjunction with the needle-nose pliers or a standard screwdriver. Be careful of the small plastic tab at the front of the connector. Also, do not drop the clips.
  4. Slide the metal clips holding the injector to the fuel rail from left to right. Push first on the front part of the clip, then the rear with the long screwdriver.
  5. Remove the fuel pressure regulator. A T-26 Torx screw and gently pry the regulator off the end of the fuel rail. It is held in by an o-ring. Mine was in there rather securely. Have an old rag underneath before removing as some gas will spill out from the rail.
  6. Remove the (2) 14mm fuel rail bolts.
  7. Carefully push the fuel rail up. The injectors are held in place now only by their o-rings, but they will be solidly in place. Work slow, maybe first at one end of the rail, then the other and it will pop up.
  8. Remove the injectors. They will still be attached either in the rail or in the intake. Either pull or *gently* pry them out.

injectors image

Before installing new injectors, compare them to the stock injectors. Make sure the o-rings are the same size; the distance between top and bottom o-rings is the same; and overall construction is similar. If all appear fine:

  1. Lightly coat the new injectors’ o-rings in motor oil to aid installation. Push the injectors into the fuel rail first.
  2. Attach/slide the clips that hold the injectors onto the fuel rail.
  3. Carefully line up the injectors into the plenum and gently push down on the rail until the bolt holes line up.
  4. Replace the (2) 14mm fuel rail bolts.
  5. Lightly coat the fuel pressure regulator o-ring with motor oil and push into the end of the rail. Replace the Torx bolt.
  6. Plug the electrical connectors onto the injectors and carefully replace the small clips.
  7. Replace the wire cover and connect the (2) 12mm bolts.
  8. Connect the battery.
  9. Turn the ignition key to the accessory position to prime the fuel pump. Check for any leaks.
  10. Start the car. Check for any leaks.

Note: If you are installing larger fuel injectors, there should be a limit to how large you can go before the stock ECU cannot scale-back the fuel delivery under idle. This could make the idle rough or cause the car to frequently stall. From personal experience, with 550cc/min injectors and a 3-bar MAP, my car idles just like stock. I have heard reports that up to 450cc/min injectors will work with the stock computer and no other modifications, but have never talked to anyone who has run their car this way as proof.

As for calculations to assist in choosing an injector size, see RC Engineering’s web site.

- write-up by Davind R. Meyers

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