Fuel Damper Leak Repair
   by Gary J Gloceri
   ganu@juno.com

Problem description:

   The problem manifests itself as a fuel leak coming from the front of the fuel rail (relative to the car), dripping slowly (at first) onto the lower intake runners. Take a look while the engine is idling. Look from the right side of the engine bay and look for a leak around and below the (usually yellowish) plastic cap that covers the damper itself.

   I think everyone should check if their damper has the same problem - seems like alot of the cars that are out there have lost the little screw from inside the damper - most likely it is sitting inside the plastic cap that sits in front of the damper. Just pop it off and check next time you are poking around the motor...(gee, do you think Mazda knew that the screws pop out so easily - hmmm maybe that is why the cap is there...) This is probably a sign that the damper is about to leak.

Replacement parts:

   The replacement damper that I used came from a 2nd gen - we weren't sure if it would fit, but it is fine (200 miles of test time so far).

David Lane (dlane@peabody.jhu.edu) suggested:

The part is listed as follows on the MAZDATRIX web site:
20-1800-JE27..PULSATION DAMPER..84-88 ALL..$ 100.60

Procedure for replacing a leaky damper:

1. GET THE RIGHT TOOL otherwise you'll spend 3 hours removing the intake manifold for no reason, except to gain access to the nut. A regular open end wrench won't work because it cannot clear the intake runners. I got a crow's foot on my 3/8 drive to fit perfectly on the bolt (I used a 7/8" but a 22mm would be better) that holds the damper in place - the first (big) budge and the damper was loose. It is a standard thread - not reversed like I presumed it might be...

2. WARNING - make sure that you do not lose the two copper washers when unscrewing the damper from the fuel rail. They are easy to lose and I would think that they are hard parts to find. Here is an ASCII diagram that Steve Brandon <brandon@acuson.com> drew for me:

                     injector                   __
                     connector                 /  __
                       |                   ___|      
   ______________| |-----| |  ____________|   |       |
                 | |     | |  \\\\          |       |
   ______________| |-----| |  ____________    |       |
   fuel rail                       damper |___|      /
                 ^         ^                  |    _/
                 |         |                   __/
               2 copper washers
   	

   Have a second person hand you the replacement while you are busy keeping the copper washers in place.

3. Carefully line up the replacement part and start the threads s-l-o-w-l-y so you don't crossthread the parts. Tighten the nut carefully.

4. Use a wire jumper to turn on your fuel pump (as described in Haynes) to test for leaks.

5. Drive away leak free... Oh, don't forget to put the cap back on.

   Let me know if anyone has the same problem or need some more specifics - easy fix - you'll spend more time finding the part then replacing it....