FPD (fuel pulsation dampner) replacement * write-up *
 

I replaced the FPD recently and it was relatively easy. I had to work in the area anyways.

The FPD part number is : N3A2-20-180

You need to remove the UIM (Dale Clark has a great write up)
http://www.clubrx.org/default.asp?id...ntent=63&mnu=5

You then have to remove the rats nest (many post on this but I plan to post another one here in a bit)

Once that is done you can see the FPD on the primary rale peaking out at you (green). If you got this far, you probably unhooked the fuel lines already and released the pressure. I also unplugged my battery for safety.
https://www.rx7club.com/forum/attach...d=179857&stc=1

You need to unhook the ACV (or at least I did). There are two 8mm bolts (with phillips heads) to remove a sensor(upper right). And THREE 10mm nuts holding the ACV onto the LIM. The top one is easy to get to *shown at top of pic. The two on the bottom aren't too bad either but makes sure you have a good hold on them as you get them out to prevent them from dropping and disappearing to never-neverland! Also it's a good idea to cover your intake ports for this very reason. You also need to unplug the sensor to the turbo control selenoid on top
https://www.rx7club.com/forum/attach...d=179858&stc=1
https://www.rx7club.com/forum/attach...d=179859&stc=1

Once that was done I found I still didn't have access to the two phillips screws that's holding the FPD into the primary rail. I ended up removing it to make it easier. There is a 17mm banjo bolt that holds the line to the primary rail. **note I have easy access to this as my airpump was removed as well as some turbo stuff**
**here it is removed in the pic**
https://www.rx7club.com/forum/attach...d=179860&stc=1

After I removed it, you can remove the primary rail from the car after unbolting it by removing two 12mm bolts. I had to work the fuel line from underneath my wiring harness. Fortunately the other side fuel tubing is very flexibile and it comes out easily. **ALSO NOTE THAT THERE IS THIS PLASTIC SPACER THING UNDER THE RAIL THAT THE BOLTS GO THRU** don't lose that.
https://www.rx7club.com/forum/attach...d=179861&stc=1

https://www.rx7club.com/forum/attach...d=179862&stc=1

There are a couple of spring clamps holding the fuel line to the FPD. Remove that. Uncrew the 2 philips screw and replaced the FPD.
https://www.rx7club.com/forum/attach...d=179863&stc=1

nice pics

here's my write-up on the FPD:

I chucked it in the garbage can and went with all braided lines :)

no adverse effects whatsoever, you only need it with rigid lines imo

this pic really drives home the point that the japanese are the masters of cluttered engine bay wiring/hose routing....at least in the early 90s

WHAT A MESS!!!!

can you (or anyone) elaborate on this? i'm in the process of a rebuild and while the car is under the knife i'm having the injectors cleaned and replacing the FPD, and i was also thinking about going to braided fuel lines.

yay old threads!

nobody has anything on this?

There is not much to elaborate on... If you want SS fuel lines (on the engine side), then you need to use an aftermarket FPD, tap the fuel rails for a AN fitting/adapter and then create/run the SS lines (on the engine side).

Not worth it unless you are going with a complete fuel system upgrade (i.e. aftermarket fuel rails, etc).

okay, thanks!

Very nice write-up. Job well done thank you.

nice pics with write up! did you check your diffusers/mixing plates under the injectors? I had one broken. Don't try to remove them if they are intact I ended up breaking the other one and droping the piece inside of the engine. Luckily I was able to fish it out with a glob of glue on the end of a stick. I think some one mentioned removing them with a bolt.

another recommendation replacing those phillips screws on the fpd with bolts. You won't have to take the whole rail off on future repairs.

I bookmarked this thread for future reference when I tackle my fpd.

WOW! great pics. If only I had this when I was changing my FPD. A few other threads were helpful enough though. I just finished today. Still have a smell under the hood, and I am deathly afraid of starting it again. Need more advice. I didn't check the injectors, lines or rails, so its gotta be one of those. Just turned the key, and went under the hood and sniffed behind the manifold. Sure enough, it still smells like gas, but its weaker.

The plastic spacer thing... that goes under the primary fuel rails bolts.... i forgot to put that back in...

anyone think ill be ok running without that? ?

The UIM is about to be re-bolted on...

The EGR is on. The nest. The coils. The fuel and water hoses...all bolted...

hmm.

I would put that spacer in. Without it, the primary injectors will not be held squarely and could leak fuel vapor.

Dave

awsum rite up