S4 vs. S5 Secondary Injector Differences
 

I'm trying to install S4 secondary fuel injectors onto an S5 upper manifold but the injectors seem too short. I have placed the diffuser (proper name?) into the injector seat in the manifold and then placed the rubber spacer on top of that. When I seat the injector in the manifold and install the fuel rail, the injector doesn't protrude far enough into the rail as the O-ring can still be seen.

Now either I'm really tired and I messed something up, or somethings going on here. Are the S4 and S5 injectors different?

Thank!

Are you installing the spacer for the primary rail?

The injectors lengths are the same. I take it you're using the S5 secondary rail? I think the S4 rail would bolt up, but clearly not fit right. You're also using the S5 diffusers too?

I had no trouble at all when I used an S5 UIM, secondary rail & diffusers with S4 injectors. They seated properly.

please take a picture and maybe mark it with ms paint to illustrate the fitment issue.

^^ +1

Good idea... I'll do this when I get home!

Diffuser and rubber spacer installed:
http://img.photobucket.com/albums/v5...t/IMG_2342.jpg

Diffuser only:
http://img.photobucket.com/albums/v5...t/IMG_2343.jpg

Injector seated at full depth:
http://img.photobucket.com/albums/v5...t/IMG_2345.jpg

Injector with fuel rail in place:
http://img.photobucket.com/albums/v5...t/IMG_2346.jpg

I think the problem may be that I'm using S4 primary injector diffusers. Can anyone tell this from the pics?

Thanks!

tighten the rail down and jumper the fuel pump diagnostic connector to verify it is leaking first (key in on position). it is the yellow two prong connector on the passenger side strut tower (may still have some insulating foam on it).

Trust me, it will leak! You can almost see the top of the fuel injector O-ring in the pic!

Do you have the thick grommet on the bottom of the injector that slips over the plastic cap?

EDIT: this,
http://i222.photobucket.com/albums/d...torgrommet.jpg

I'll take a picture tomorrow of the rail/injectors on my S4 NA engine that has the S5 manifold swapped on. Your injectors are definitely sitting way too low.

Looks like it's missing the grommet or the fuel rail is secondary fuel rail is different.

Your problem is the S4 diffusers, which are not meant to be used with S5 air bleeds. The S5 diffusers are taller, and have 2 o-rings. Take a look at the difference here: http://www.mazdatrix.com/c-6.htm.

This is what it should look like with an S5 rail, S5 UIM, S5 bleeds/diffusers & S4 injectors. You can see the rubber grommet sticking up out of the manifold.
http://members.cox.net/linspace/s4inj_s5rail.JPG

For what it's worth, the lower grommet on a seires five is different size than the grommet for a series four.

true!

s4 is n326-13-257 s5 is n350-13-257