Rob Edwards

I'm in the buttoning up stage here, am re-assembling the throttle body and will be putting the intake back on once I re-learn where all the vacuum lines are routed (took lots of pics).

Since many people change out injectors without pulling the intake, obviously one could reinstall the intake and then the injectors. Alternatively, I could put them in the intake while still on the bench and then install the intake. Is there any particular 'best way' here? My biggest concern is getting them seated properly so I don't burn the car and house down on startup....

Jim M.

When your ready to start it for the first time, pressurize the fuel rails and injectors before applying ignition. Check for fuel leaks then add ignition.

Jim Mayzurk
93 GTS 5-spd

RyanPerrella

yeah no problem, you have to wiggle the injectors into the manifold and they are really held in with a portion of the intake gasket. You must remove the rail to bolt down the intake though.

Hey Rob, my cars all put back together now, but where you are now maybe you can help, you think that i can remove and replace the idle stabilizer with the intake still attached and just the maf and air cleaner removed? I dont know how i could do it honestly, but i dont really want to remove the intake again to replace something that may not even be the problem.

Mrmerlin

I think its easier to install the intake first , as the hold down bolts are hard to get to otherwise, when your doing it this way make sure that the intake gasket is seated around the metal collars that slide over the studs, also make sure the thicker rubber hoses are routed alongside the lower portion of the intake that sits in the valley its easy to pinch these lines if your not careful, and be careful around the throttle junction the lines can sometimes catch or interfere with the throttle cable function, it will be easier too if the injectors are out of the way, it is a good idea to have an extra set of hands to help lower the intake as the various lines are fed through the intake, and lastly it is a good idea to use a lubricant like silicone grease on the injector O rings this helps them find their home once they are positioned in the intake and fuel rails, also check that the intake gasket is in the right position to allow the injector to spray into the intake port, make sure the flappy valve is new and the TPS is as well and that they are functioning as they should IE the Flappy should not bind when its closed and when its time for it to open (check this system with a vacuum or by sucking lightly with your mouth)and the positioning nut should have a dab of locktite setting fluid so it stays where you set it. The TPS should be set so that just as the throttle plates are moved you should hear the switch clicking from the fully closed position. if you didnt do it you should also have replaced both knock sensors and the ignition timing pickup that goes into the top of the engine just above the flywheel, and the ICV should be near new or cleaned out, and as always the oil fill should have a new O ring placed on its mounting point to the block, these pieces being new will prevent the intake from having to be removed in a year or 2 when they fail, Ahh one other thing if you have not done so now is the time to replace the fuel lines that are routed on the engine there are 4 of them Good luck to you, Stan

Mrmerlin

Ryan you can remove the ISV by laying on the engine and with your smallest set of hands trying to get up under the rear of the intake , this is PITA , removal of the MAF will greatly help

Rob Edwards

Stan-

Thanks, I've got everything except the ISV connection made, and I have the tool for it, so we're close.

Ryan-

Maybe Stan's got size 5 hands with a pinky missing or something, but I (size 8.5, all fingers present) really don't think be possible. The ISV is held in a bracket with 2 -10mm nuts that attach to rubber-isolated posts on the underside of the throttle body. The two hoses that come out of the ISV are large diameter and are tough to get seated on the nipples even on the benchtop.

Mrmerlin

Well as far as the ISV goes i think Bill Ball replaced one in the car and I know Dave Lomas at Motorsport did as well its a tricky deal and it does take laying on the motor to see whats going on, and i dont believe that you fully remove the clamp bracket just loosen it and remove one bolt

worf928

The most fool-proof (i.e. no fuel leaks when you are done) way to install the injectors is to clip them into the rails and then install the rails. If you insert the injectors into the intake first and then try to install the rails it will be more difficult to get the top o-rings to seat.

Make sure, also, that you put a little lubrication on the o-rings. You can use vasoline or motor oil.

Rob Edwards

Thanks for all the posts, and thanks to Dave again for the great intake instructions! I will have to write up my intake re-installation for dummies when I get this finished!

I had the injectors refurbed by Witchhunter, which included a new set of o-rings top and bottom. With the intake manifold bolts still loose, I put the injectors in individually after putting some silicone grease on the o-rings and checking that the rubber 'U' of the intake manifold gaskets were aligned. They slipped in rather easily, so easily that I was paranoid that the o-rings they installed were too small, so I checked them with a mic- ~16.5 mm OD by ~4.8 mm thick, which was the same as the old o-rings that were on them (and the same as the new Bosch o-rings that I bought thinking I'd need them....)

Anyway, I then coated the top o-rings with silicone grease and installed the fuel rails (I also put a very light coat of grease in the 'cups' on the underside ot the rails. There seems to be a bit for lateral play in the injectorsr until you tighten the 10mm nuts on the rail mounts and also the fuel connections at both ends of the rail. In any case, it's all together and the injectors appear to be seated properly.

I can't fire the car up until the MAF comes back from Colorado- will probably push the car out of the garage and have the fire extinguishers ready on fire up. It's a little unnerving not to have proper torque values for the 10+ un-gasketed joints where the fuel system connects........

worf928

Pull the fuel pump relay and bypass it with a jumper wire to activate the pump and flow fuel through the rails. That's an easy and relatively safe way to check for leaks - no spark.

Rob Edwards

Dave-

I jumpered the pump relay (who hid it behind the LH brain?) and connected the battery - fuel spewed all over the place from the top of injector #3- Back to the drawing board. I'll pull the rail on that side and attach the injectors to the rail and reinstall while all the gas evaporates.......

Everything else looked ok (during the 15 seconds the rail was pressurized) but will definitely recheck before running it.

Yikes!

-Rob

Bill Ball

I have small hands but I can't see how the ISV could be installed with the intake on except perhaps on an 85-86. It is way deep under there. I had a load of trouble just getting the hose fittings into the throttle boot and a few vacuum hoses onto the throttle body.

Bill Ball

My preference is to clip the injectors into the rail and then install the rail. Lube the lower o-rings with silicone grease. Carefully line up the injector tips with the manifold and push/wiggle the rail until the tips work themselves in and the rail is seated on its mounting studs, checking as you go to make sure none of the o-rings get pinched.

A little trick to get the fuel rail M6 nuts & washers on the studs: Put them on a long, thin screwdriver blade and hold onto them as you drop the tip of the screwdriver onto the stud. Release the nut and washer and they will slide down the screwdriver onto the stud. Continue to hold the tip of the screwdriver on the stud as you reach down with a finger tip and spin the nut until it starts to thread onto the stud. No more dropped nuts and washers!

After the rails are reattached, power up the pump and check for leaks.

Rob Edwards

I think that my mistake was actaully the positioning of the clips onto the injector and the rail. The #3 injector clip was not properly positioned in the grooves on the injector body, so that was probably it. Hopefully it'll work on take #2.

I'm discovering new ways to make more work of this than necessary- for the newbs, disconnect the injector harness lead from the injectors BEFORE lossening the fuel rail. otherwise you can't generate enough force to remove the connector (they are ridiculously tight- I have #2 (partially blocked by the forward breather hose, the fuel feed line, etc) out of the manifold and cannot remove the connector. I will have to install the rail into place to hold it so I can disconnect the damn connector. And this is with the 9266 tool....

Bill Ball

I agree about removing the harness plugs first and putting them back on last. Some people find thay have to fight with them. I don't use a tool. If you wiggle them gently side-to-side, they will unclip on their own. Also, be careful to watch the wire clips as you remove the plug. They are held on by a tiny shard of melted plastic that often fractures and allows the wire to shoot off into space.