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Since so many of you have asked on how to replace the secret filter I am reposting this info. The post is not on the repair link anymore.


Sooner or later, the screen filters will have to be replaced. Most motors will experience a loss in rpm or poor acceleration - not reaching full potential. The complete job takes less than a couple of hrs.

After disconnecting the main battery terminal and unplugging the boots from the spark plugs remove the coil cover and support it so it doesn’t hang on the ECU electrical connections.

Remove the gray hose from either side between the plates and all bolts identified with a red X. Fold the starboard fuel rail pressure line away from the plate. The port side plate can be folded away with the fuel rail line still attached. To remove the plates, carefully pull and pry away from the main body of the pump. The only thing that is holding the plates at this point are the o-rings on two large fuel pipes inside. These o-rings are the same size as the ones on your injectors. The screens are located behind these fuel pipes identified in pic2 with O.
Use a tightly fitted screw and washer to remove the screens as shown in pic 3 & 4. I found that using dikes on the neck of the screw will easily pop the screens out.
There are four screens to replace (one in each large fuel pipe cavity) and these are the same size screens as in your injectors. You can obtain replacements from an injector shop like Brucato or Hydrotec for little or nothing.
The o-rings should not have to be replaced unless there are visible tears or cuts on them. Install new screens using a fitted punch or something suitable that spans over the brass edge and tap them back into the cavity. Replace the fuel pipes with large o-rings with some oil on them and press the cover plates back on. Use red loc-tite on the cover plate bolts and fuel rail hose fittings. I don’t have the torque specs so don’t over tighten as the assembly is made from aluminum. Replace the coil cover with plug wires and you’re done.

TIP; if you happen to pull the screen out without the brass neck on the screen, carefully screw in a tapered 6mm tap to remove the brass from the cavity.
A small amount of fuel will spill when removing the plates so have some shop towels handy.
Avoid static electricity; each time you are near the motor touch a good ground source before touching any fuel related components.

Moderator, please pin this page in the repair link.