Question re installing fuel injectors
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Joined: Oct 2009
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Question re installing fuel injectors
I'm planning to replace the stock fuel injectors in my 1990 L98 engine with Bosch III's from FIC. Everything I have read says I have to remove the fuel rails. Question: Can the injectors be removed with the fuel rails in place? In order to remove the fuel rails, I'd have to remove the intake manifolds because the fuel rails are under them. To remove the intake manifolds, one of the torx bolts holding them in place is squarely behind an injector. Since the injectors appear to be held in place by their snug fit and O-rings, can't they simply be removed from the rail with it still in place? Thanks...
Burning Brakes
Joined: Mar 2010
Posts: 1,094
Likes: 68
From: Providence RI
the oem multecs have little clips that hold them in the fuel rails so the rails do need to come off in order to swap the injectors.
The new bosh 3's dont need the clips.
When I did injectors on my 91, i took off the plenum and runners then the fuel rail as a whole assembly.
A few long extensions help out a lot. The torx bolts are possible to get to, but not all that easy.
The new bosh 3's dont need the clips.
When I did injectors on my 91, i took off the plenum and runners then the fuel rail as a whole assembly.
A few long extensions help out a lot. The torx bolts are possible to get to, but not all that easy.
Last edited by Deepa; Apr 26, 2010 at 11:59 AM.
Racer
Joined: Jan 2007
Posts: 322
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From: Chapin South Carolina
It is impossible. The clips are underneath the fuel rail. I did mine a few weeks ago and I feel your pain but you can get to them all. You just have to remove a lot of pieces which makes it easier in the end. There are two bolts going in from behind that are the hardest to deal with but they also can be done. Note: you need to remove the passenger side plenum but the driver's side just needs to be loose.
Le Mans Master
Joined: Jul 2007
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From: No HOA, New Hampshire
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St. Jude Donor '09
I was intimidated when I did the same swap on my 88. 1/4 drive ratchet with extensions and a swivel are a must. After you do it once, it is easy and quick.
Race Director
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From: Overland Park Kansas
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Le Mans Master
Joined: Oct 2008
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From: Houston Texas
It is impossible. The clips are underneath the fuel rail. I did mine a few weeks ago and I feel your pain but you can get to them all. You just have to remove a lot of pieces which makes it easier in the end. There are two bolts going in from behind that are the hardest to deal with but they also can be done. Note: you need to remove the passenger side plenum but the driver's side just needs to be loose.
It has been done before but it would be a PITA.
Safety Car
Joined: Jan 2008
Posts: 3,939
Likes: 1
From: Vero Beach Florida
If you want my advise I would take it all down and do the intake gasket at the same time. Clean it all up and you will be ready to go. A year after I did my injectors I was doing the intake gasket, so I was redoing the same work.
Advanced
Joined: Jun 2009
Posts: 95
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From: Rochester NY
I just swapped some of mine using some multecs I bought from Gregg. Like he said here too, he advised me to reinstall without the clips and that's what I did. Good thing, because in the heat of the moment I put the whole thing back together to find that one injector is almost dead. Hopefully tonight I should be able to put a different one in its spot without much difficulty.
To do my swap, I:
EDIT - also wanted to add that the bolts holding down the rails were TIGHT! An open ended wrench just bent and slipped around the bolt, not even rounding it over, and I don't have a 10mm 12pt box. Grabbed a 10mm 6pt box combo wrench and it did the job.
To do my swap, I:
- Removed the plenum completely, disconnecting all the vacuum connections, sensors, and the throttle body.
- Removed the EGR valve to get more room to move the rails around.
- Disconnected the fuel lines in front of the engine, and the bracket holding the lines in place.
- Completely pulled the driver's rail, and rotated the passenger's rail enough to swap while in place.
EDIT - also wanted to add that the bolts holding down the rails were TIGHT! An open ended wrench just bent and slipped around the bolt, not even rounding it over, and I don't have a 10mm 12pt box. Grabbed a 10mm 6pt box combo wrench and it did the job.
Last edited by whitebrow; Apr 27, 2010 at 09:26 PM.