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!
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
- 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:
- Disconnect the battery.
- Remove the (2) 12mm bolts holding the black plastic wire cover.
- 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
- 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.
- 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.
- Remove the (2) 14mm fuel rail bolts.
- 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.
- Remove the injectors. They will still be attached either in the rail or in
the intake. Either pull or *gently* pry them out.
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:
- Lightly coat the new injectors’ o-rings in motor oil to aid installation.
Push the injectors into the fuel rail first.
- Attach/slide the clips that hold the injectors onto the fuel rail.
- Carefully line up the injectors into the plenum and gently push down on the
rail until the bolt holes line up.
- Replace the (2) 14mm fuel rail bolts.
- Lightly coat the fuel pressure regulator o-ring with motor oil and push into
the end of the rail. Replace the Torx bolt.
- Plug the electrical connectors onto the injectors and carefully replace the
- Replace the wire cover and connect the (2) 12mm bolts.
- Connect the battery.
- Turn the ignition key to the accessory position to prime the fuel pump. Check
for any leaks.
- 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