View Full Version : Need my Memory Refreshed Guys

Les Borda
08-05-2014, 12:13 PM
I have a fair sized job coming up on my sons 90 SC, which includes changing injectors. I have done this a number of times but not for a long time. I have CRS (can't remember shyte).

Correct me please.

Remove old air box rubber hose and old MAF(SCPeformance one going in) and 80mm ProM maf.
Remove old TB, take heater hoses off and put in a bypass hose.70mm BBK going in and have to move over the IAC and TPS.

Uhhh can I just take out the 4 bolts for the plenum at the back of the blower, unbolt the blower and remove it to access the fuel rail? I know upper IC tube has to be undone and probably removed.

There c clips on each injector along the fuel rail and are reused on the new injectors?

Thanks guys appreciate what I may have left out or is in the wrong order.

08-05-2014, 12:37 PM
This is copied/collected from other threads here - I haven't personally validated...yet:

Remove air intake tube
Remove wipers/cowlings to gain more access across the back of the engine...you might gain more still if you remove the wiper drive mechanism
Remove vacuum hoses from Intake plenum and TB linkage - mark/photo for correct reassembly
Remove belt from SC
Remove SC, plenum, throttle body (engine coolant hoses at TB?) and upper IC tube (unless you have the correct OTC spanner for the upper collar & don't want to unbolt it from the accy. bracket) all together as one unit. Be ready for re-assembly with black RTV and telfon gaskets as desired) and don't forget the EGR on the back if so cursed carefull...that thing is a pain to get to and easy to damage when old. Dorman sells new, I think.
Remove Fuel rail bolts - they can be very tight so be sure to use the right torx bit...size? Have seen some break off in the manifold so be patient. I would try to remove the rail with the injectors in place, and then unclip them later. Clips are reusable, but discard/replaced if damaged. This might be a good time to renew the flexible tubing that is part of the rail assembly. Victor sells tubing and refurb'd rails. Grab a fuel line tool to uncouple at the fittings on the tank lines.
Unbolt FPR? see below

Take your time when removing the electronic connector on top of the injectors. They have a plastic clip holding them on and they are pretty brittle and will break fairly easy.
Put some oil on the O-rings on each injector and remove and install one at a time.
Re-assemble - I also put a few worm clamps on a couple of the vacuum lines.
Might want to replace the fuel filter just to round things out.
Check torque on intake manifold bolts...might want to set higher than stock spec...?


I think you will have to remove the inlet elbow from the lower intake manifold, as the fuel rail actually snakes under and around it (near the fuel pressure regulator). There is a bolt that mounts the FPR to the rear of the driver side cylinder head. It can be tricky to get to, but it needs to come out if you're going to actually lift the fuel rail off the injectors. However, you should be able to leave the lower IC tube in place once you've disconnected it from the inlet elbow, which means you can leave the driver side accessory bracket alone.

Don't forget to discharge the fuel pressure in the rails via the schrader valve, or by disabling the fuel pump (via the fuel pump cutoff switch in the trunk) and cranking over the engine. Also, you should disconnect the battery before you start the disassembly, since you'll have some raw fuel on the top of the engine, and make sure you reconnect it once you get the new injectors and the fuel rail back in place, so that you can cycle the fuel pump on and off a few times to check for leaks on the top side of each injector.

David Neibert
08-05-2014, 12:47 PM

I always did it like this.

removed the top and upper IC tube as a single unit.
remove the supercharger belt from supercharger pulley
remove air intake pipe between MAF and TB
unplug IAC and TPS
disconnect spark plug wires from coil pack for cyl 1,2 & 3 and lay toward passenger side of motor
loosen hose clamps on bypass valve to returm plenum coupler
disconnect throttle cable, TV cable and cruise control cables from throttle linkage
unbolt throttle cable mounting bracket from side of inlet plenum
remove the 3 supercharger retaining bolts
lift supercharger up and wiggle a little to get out of bypass valve connecting hose
pull forward a couple inches to make room for disconnecting vacuum hoses from the back of the inlet plenum
remove supercharger assembly with inlet plenum and TB still attached.

next unplug the connector to the air charge temp sensor and unbolt the return plenum from the intake manifold. Once unbolted you can remove vaccum lines going to fuel pressure regulator and boost gauge. Then set aside.

At this point you should have easy access to the fuel rail retaining bolts. If original there will be a bolt holding the rail to the back side of the driver's side head. Once removed discard it because it not really needed to support the rail. Once unbolted you should be able to wiggle the entire rail around while pulling upward to pull injectors out of the heads while still attached to the rail.

Now you just need to relieve fuel pressure by disconnecting the lines or pressing in the shrader valve. Injectors can then be swapped one at a time. I like putting a little lube on the injector orings, to make installing easier.

Then just put it all back together in reverse order, using high temp RTV to reseal the return plenum and IC tube/SC top. I would also recommend using zip ties on all vacuum hose connections.


08-05-2014, 12:48 PM
I would disconnect the top SC tube at the intercooler, but leave it on the SC top. If the bold is there still to support the intercooler you can remove the nut and remove the stud.

I would disconnect the air filter top, unconnect the throttle body linkage, wires, and maf connector. Pull the air filter top with maf attached and intake hose and set it aside.
Unbolt the blower, remove the belt, and lift the blower with the inlet plenum and throttle body attached directly off along with the top and the top tube.

Now you can access the fuel rail though you can't remove it without pulling the plenum attached to the intake manifold (I think). Also the rail has a bolt into the drivers side head on the back of that plenum that can be a pain to remove.

Les Borda
08-05-2014, 01:37 PM
Thanks guys!!!

Dave I remember now about loosening the bypass hose clamp and wiggling the charger out of the bypass hose, as soon I saw you say that a light bulb glowed partially dim LOL. Also recall that one unnecessary fuel rail bolt.

Tim Groth
08-05-2014, 02:27 PM
Thanks guys!!!

Dave I remember now about loosening the bypass hose clamp and wiggling the charger out of the bypass hose, as soon I saw you say that a light bulb glowed partially dim LOL. Also recall that one unnecessary fuel rail bolt.

I always try to remove the Supercharger with the upper IC tube and Top still attached...along with the Inlet Plenum and the TB. You do have the coolant connections on the TB also. Unplug sensors, unbolt the EGR, Take off the Belt, remove 3 bolts...might still have the 1 bastard bolt by the battery (lower side of the IC pipe).

Otherwise everthing you posted sounds right.

Also I am pretty certain you have to remove the rear intake plenum piece too to get to the rear fuel rail bolt on that car. One that mounts it to the head..which is a total pain in the *** with the coolant hose running on the back of the heads. You'll have to remove that coolant hose for the TB off the heads to get that bolt out - probably the worse part of the job.

also you left off 12 pack of beer.

Good luck.


Kurt K
08-05-2014, 02:32 PM
You guys are all scared. I have always removed the upper IC tube from the top and IC when doing this type of work. My OTC spanner wrench is well used.

Les Borda
08-05-2014, 04:10 PM
I always removed the collar nut as well, I don;t have the tool but short chunk of 2x4 work nicely to loosen, or I have this enormous Snap On flat blade that oddly enough I found behind the back seat of my XR7 way back when...a gift LOL. I pad one of the collar nut notches and give it a whack or two and it loosens,

Someone did say remove the EGR didn't they, I hate that, that and that stupid silicone tube to the EGR sensor which gets shorter each time you take it off.

I ran nitro RC monster trucks and build them i have silicon tubing that is Nitro proof and heat I just don't know how high of a temp. The head on those nitro motors get extremely hot and this tubing can lay right against it. Hopefully not required.

08-05-2014, 04:15 PM
I don't see a need to remove it completely unless you have no choice. Just disconnect at the intake manifold if you can get back in there. Otherwise work the lower end at the exhaust manifold instead. Neither is fun.

Les Borda
08-05-2014, 04:21 PM
Thanks KMT I kind of remember just undoing it at the intake not too bad to take off.

08-05-2014, 05:07 PM
Since the top tube usually has to come off anyway, I always just removed it and the SC top as an assembly. Easier to reseal things that way.

08-05-2014, 07:37 PM
You guys are all scared. I have always removed the upper IC tube from the top and IC when doing this type of work. My OTC spanner wrench is well used.

For me, one stripped SC top bolt is one too many. :)

I also like pulling the SC, top pipe, inlet plenum, and TB as a unit. Just easier for me and less hassle. Kind of a bear getting it all back in place, but then you can't easily bolt the inlet plenum back on the SC when it's on the engine anyway. So might as well get it all together in comfort and then drop it in as a unit.

08-05-2014, 08:23 PM

I always take the hat and tube off as one piece separate from the blower.

They have got guaranteed memory for the reinstall.

Just hit it fairly hard with RTV and it's painless.

The blower. Intake plenum and TB are a bit of a handful to rock back into place as is.

Depending on tools the rail bolt at the back of the head I believe can be gotten from down below.

On originals it will probably snap off.

If you try this first you won't have to do the return plenum.

The EGR will be all 1/4 inch work with extensions and swivel's.

It's the one piece that justifies owning a 5 speed.

Keep track of your vac lines.

It goes without saying all your cowling is coming off.