84-88 Fuel Pulsation Dampner Elimination
RX-7s made during this time frame had a small round device on the primary(lower) fuel rail called a pulsation dampner, or PD/FPD for short. Often these fail allowing raw fuel to be shot out, which then runs down the side of the engine onto the hot exhaust manifold. Many junkyard rx-7s died a fiery death because of this, and many owners have had their cars catch fire spontaneously due to this. However, there is a simple and cheap permanent fix with no side effects for the owner who wants to take the time to correct the condition. Here are directions:

1. obtain a spare primary fuel rail from an 86-88 non turbo engine. Note the FPD on one end, (the larger mushroom shaped part) and the banjo bolt on the other end(hollow bolt). Remove the banjo bolt (banjo bolt size is 12mm x 1.25) and discard the rail. See image 1.

2. Remove the primary rail from your car. You will need to remove the intercooler(turbo models), upper intake, middle intake(nonturbo models), and assorted hoses, cables, and wires to do so. The lower fuel rail is bolted to the pass. Side of the block, where the intake mates to the engine.

3. remove your FPD from your fuel rail. See images 2 and 3.

4. install the banjo bolt you removed from the spare rail into your rail. Be sure to use both copper crush washers and tighten this bolt down well. See image 4.

Put it all back together. Be sure to get the fuel lines and injectors seated and tight, and inspect for leaks. See image 5.


Image 1.

Image 2.

Image 3.

Image 4.

Image 5.

Injector Information
Fuel Cut Off Switch & Unflooding Procedures
Rebuilt Engine Start Up and Break In Procedures
N/A to TII Conversion
Automatic to Manual Transmission Conversion,

1984-1988 Pulsation Dampner
Airpump 6 PI

Internal Engine Damage
Coolant Seal Fix
ECU Application List
Engine Removal
Engine Teardown: Longblock to Shortblock
Series 4 to Series 5 Engine Swap
Series 5 to Series 4 Engine Swap
Emissions Removal
Compression Check

Cone Filter/Intake Modification
Electric Fan
Electric 6 Port Conversion
Series 4 turbo engine emissions removal
Series 5 turbo engine emissions removal
Water injection treatment for all rotary engines
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