Injectors - How To Remove/replace/upgrade

[MearCat]

I thought it about time to do a DIY for removing/replacing/upgrading injectors in a RB25 series engine. These photos were done my my Series 2 R33, but it should apply to most RB's I expect

Contrary to some posts I've seen, there is NO need to crack open the intake plenum to get to your injectors You only need to remove the AAC assembly and throttle body (and possibly FMIC piping).

The entire process should take you ~2 hours depending on your confidence/skills.

1) Remove AAC assembly. There is a DIY thread (HERE) on this but in this case, you only need to remove the AAC from the manifold, not pull it apart. Remove 3 hoses from AAC (circled in red) and loosen 3 bolts that hole AAC onto the manifold. There is no need to remove the hose from underneath the AAC unless you intend on removing and cleaning it.

2) Remove 3 bolts from AAC assembly. One bolt is circled in blue in above pic, but the other two are hidden underneath. Swing AAC away to the side. If the AAC is dirty inside, I suggest cleaning it as per AAC cleaning thread above.

3) Remove metal intake pipe. Remove 2 bolts from pipe bracket and loosen BOV recirc pipe (RHS of pic). Undo clamps that connect intake pipe to the throttle body, including one small hose that connects directly above the throttle body. Move intake pipe away from throttle body assembly.

4) Remove 4 bolts that hold the throttle body on and remove three other hoses (circled in red)

5) Undo a multitude of hoses (red circles) and unbolt the two bolts circled in blue. If you have a FMIC kit, take this opportunity to remove the pipe that runs over the radiator fan. You won't be able to get the injector rail out otherwise.

6) Undo 3 bolts holding the injector rail onto the manifold. You will be able to get to 2 of these with a ratchet, but one will need a spanner. BE CAREFUL - each bolt has a plastic spacer between the injector rail tab and manifold which can be easily dislodged and lost. Remove these and keep for when you are bolt the rail back on. Check (if you live in usa): Costco Weekly Ad, or Supercheap Auto Catalogue.

7) The injector rail will be able to be removed now. BE CAREFUL AGAIN - Each injector pintle is inserted into a rubber ring which can also be easily dislodged. DO NOT lose these. After the rail has been removed from the, reach in and unplug each injector (you kind of need nimble hands for this). Carefully remove injector rail by lifting and sliding out towards the front of the car.

8) For each injector, remove the two screws (with Philips head) from the injector cover and take off. These screws will more than likely be tight.

9) To remove the injector... If you don't have an injector puller (which most of us don't), the CAREFULLY insert a screwdriver wrapped in rag into the hole at the top of injector and lever it out of the rail.

10) To fit injectors into rail, put a small amount of grease on the o-ring and place injectors into rail and place cover on the top of it. Only use rubber grease as some industrial greases will eat rubber and that can lead to disaster. Don't try to push injectors into rail, as the cover with push it into place as you tighten the screws.

11) Put rail back into engine bay, ensureing that rubber pintle surrounds are in place, plastic spacer rings for the rail bolts are in place, injector plugs are plugged in, all hoses and clamps are replaced and tightened.

Thanks for reading!

-Alan

Edited March 13, 2008 by MearCat

[Reckless Motor Sport]

Thanks Alan just doing mine so this guide will help alot

In the pic above i want to remove the part in the red circle so that i can get the fuel rail re-dipped mine looks bad should this part just pull out.

Also was the fuel rail you used off an rb25de non turbo model

[MearCat]

The fuel pressure regulator on the end of the rail can be removed by undoing 2 screws, leaving the rail bare.

My car/fuel rail (and all thepics) is a turbo model.

[BAMR33]

Noice, this will be excellent for me in a couple weeks time.

Also great work with attaching pics rather hosting them.

[Lazy-Bastard]

Nice work. Will come in handy for me too in a couple of weeks.

One comment though.......YOUR ENGINE BAY IS FAR TOO CLEAN!!!!

[R32_GODZILLA]

Excellent write up - this will come in handy for me soon, as i'll be replacing a couple of injectors on my RB20 - hopefully not too disimilar.

Cheers,

Steve.

[Topaz]

Excellent write up - this will come in handy for me soon, as i'll be replacing a couple of injectors on my RB20 - hopefully not too disimilar.

Cheers,

Steve.

R32 fuel rails are slightly different, at aleast on a GTR they are. But you wil be able to use this toot for getting at the fuel rail at least because you have the over the engine plenum intake.

[pshht]

well done mate excellent write up.. im doing this next week. cheers for the info

[Devils_Advocate21]

Gotta ask how the hell do u remove a screw that the head has been fully burred out of one of the pintile caps holding the injector in place best possible method.

Cheers Adam

[Trooper]

Gotta ask how the hell do u remove a screw that the head has been fully burred out of one of the pintile caps holding the injector in place best possible method.

Cheers Adam

But a screw extraction tool if there is no other way to get it out. Bunnings etc sell them.

Or you can cut a slit in the top of the head and use a flat head screwdrive to pull it out.

[Drivebai]

Awesome writeup mate,

Got quoted $320 from the tuners to install injectors for me..

You have saved me $320

Thanks mate.

[SkyKC]

I thought it about time to do a DIY for removing/replacing/upgrading injectors in a RB25 series engine. These photos were done my my Series 2 R33, but it should apply to most RB's I expect

Contrary to some posts I've seen, there is NO need to crack open the intake plenum to get to your injectors You only need to remove the AAC assembly and throttle body (and possibly FMIC piping).

The entire process should take you ~2 hours depending on your confidence/skills.

1) Remove AAC assembly. There is a DIY thread (HERE) on this but in this case, you only need to remove the AAC from the manifold, not pull it apart. Remove 3 hoses from AAC (circled in red) and loosen 3 bolts that hole AAC onto the manifold. There is no need to remove the hose from underneath the AAC unless you intend on removing and cleaning it.

2) Remove 3 bolts from AAC assembly. One bolt is circled in blue in above pic, but the other two are hidden underneath. Swing AAC away to the side. If the AAC is dirty inside, I suggest cleaning it as per AAC cleaning thread above.

3) Remove metal intake pipe. Remove 2 bolts from pipe bracket and loosen BOV recirc pipe (RHS of pic). Undo clamps that connect intake pipe to the throttle body, including one small hose that connects directly above the throttle body. Move intake pipe away from throttle body assembly.

4) Remove 4 bolts that hold the throttle body on and remove three other hoses (circled in red)

5) Undo a multitude of hoses (red circles) and unbolt the two bolts circled in blue. If you have a FMIC kit, take this opportunity to remove the pipe that runs over the radiator fan. You won't be able to get the injector rail out otherwise.

6) Undo 3 bolts holding the injector rail onto the manifold. You will be able to get to 2 of these with a ratchet, but one will need a spanner. BE CAREFUL - each bolt has a plastic spacer between the injector rail tab and manifold which can be easily dislodged and lost. Remove these and keep for when you are bolt the rail back on.

7) The injector rail will be able to be removed now. BE CAREFUL AGAIN - Each injector pintle is inserted into a rubber ring which can also be easily dislodged. DO NOT lose these. After the rail has been removed from the, reach in and unplug each injector (you kind of need nimble hands for this). Carefully remove injector rail by lifting and sliding out towards the front of the car.

8) For each injector, remove the two screws (with Philips head) from the injector cover and take off. These screws will more than likely be tight.

9) To remove the injector... If you don't have an injector puller (which most of us don't), the CAREFULLY insert a screwdriver wrapped in rag into the hole at the top of injector and lever it out of the rail.

10) To fit injectors into rail, place injectors into rail and place cover on the top of it. Don't try to push injectors into rail, as the cover with push it into place as you tighten the screws

11) Put rail back into engine bay, ensureing that rubber pintle surrounds are in place, plastic spacer rings for the rail bolts are in place, injector plugs are plugged in, all hoses and clamps are replaced and tightened.

Thanks for reading!

-Alan

Can youn please re add the pictures please...................?

[MearCat]

The pics have been uploaded and re-attached

SkyKC - can you please get rid of the massive quote of my original post in yours please.

[Birnie]

Gotta ask how the hell do u remove a screw that the head has been fully burred out of one of the pintile caps holding the injector in place best possible method.

Cheers Adam

Yeah, these babies were tight!

Not enough down pressure or crappy screwdrivers and GONE!

I ruined 2 screws out of the 12 so it's prett easy to do.

Grabbed my trusty hacksaw and sawed a slit in the top, straight out with a flathead screwdriver

Awesome writeup mate,

Got quoted $320 from the tuners to install injectors for me..

You have saved me $320

Thanks mate.

Agreed, awesome write up.

In and out took me a touch over 4 hrs for a 1st timer.

$320/4 = $80 an hour.... Cool ! Feels awesome to save that cash!

It's like getting a free boost controller! LOL

[MKDR33]

does the stock ECU adjust itself accordingly to suit the new injectors? or do u have to tune/replace the ECU aswell?

Edited April 29, 2007 by MKDR33

[Lazy-Bastard]

Yeah, these babies were tight!

Not enough down pressure or crappy screwdrivers and GONE!

I ruined 2 screws out of the 12 so it's prett easy to do.

Grabbed my trusty hacksaw and sawed a slit in the top, straight out with a flathead screwdriver

Agreed, awesome write up.

In and out took me a touch over 4 hrs for a 1st timer.

$320/4 = $80 an hour.... Cool ! Feels awesome to save that cash!

It's like getting a free boost controller! LOL

For anyone else giving this a go...To avoid rounding the screws that hold the injector "hats" in place, stick a stubby screwdriver in the screw and give it a good whack with a hammer. This should break the seal on the screw and they come out easily.

[Musky]

does the stock ECU adjust itself accordingly to suit the new injectors? or do u have to tune/replace the ECU aswell?

i'd liek to know this too...

[adam-__-]

You would have to change the settings on your ecu or get a remap done.

Cheers,

Adam

[Blitz_boy]

Do you need to lube up the rubber o-rings before putting the new ones in? If so what lube do you use (no jokes please)

[MearCat]

Do you need to lube up the rubber o-rings before putting the new ones in? If so what lube do you use (no jokes please)

Not sure whether it's mandatory or not, but I just put a tiny amount of generic grease around mine.