fuel injectors
Instructor
Joined: Apr 2005
Posts: 141
Likes: 0
From: Downers Grove IL
Use the GM manual from www.helminc.com or go to MidAmerica and get the service manual and electrical manual set. Helm may not have the complete set all the time. Hayes also as a nice manual that maybe availaible at your local AutoZone. The GM manual gives you all the details and the hayes shows you at lease one good shortcut. I have both and then there is this forum that will help when the manuals fail.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
I remove the plenum, TB, runners and fuel rail when changing injectors.
If you have not done the TB coolant bypass mod you will need to drain a little coolant and remove the two coolant hoses from the TB. Use care removing/installing the hard plastic vacuum hose under the TB and in handling any of the hard vacuum hoses.
You may need to rap on the plenum with a rubber mallet if it hasn't been off before.
Depress the spring clip on the injector connector and pull the connector from the injector.
I remove the EGR tube to gain access to the bolt that holds the inner rear of the left runner base. The bolt holding the inner front of the right runner base is easy to access.
Each injector is held into the fuel rail by a clip that must be rotated before the injector can be pulled from the fuel rail; use care as these clips are easy to break. Apply a little motor oil on each new injector O-ring to avoid nicking one on installation. Clean the injector holes in the base of debris.
If the fuel lines seep fuel too long, loop a section of heater hose between them and clamp both ends tightly. If you have under 1/4 tank of fuel this may not be an issue.
If you look over your TPI setup carefully you will see how to preceed; bagging/labeling the bolts will greatly help on assembly. If you are new to this procedure a few digi pics taken along the way might be useful too.
Get an intake gasket set for your L98 from Auto Zone and have at it.
If you have not done the TB coolant bypass mod you will need to drain a little coolant and remove the two coolant hoses from the TB. Use care removing/installing the hard plastic vacuum hose under the TB and in handling any of the hard vacuum hoses.
You may need to rap on the plenum with a rubber mallet if it hasn't been off before.
Depress the spring clip on the injector connector and pull the connector from the injector.
I remove the EGR tube to gain access to the bolt that holds the inner rear of the left runner base. The bolt holding the inner front of the right runner base is easy to access.
Each injector is held into the fuel rail by a clip that must be rotated before the injector can be pulled from the fuel rail; use care as these clips are easy to break. Apply a little motor oil on each new injector O-ring to avoid nicking one on installation. Clean the injector holes in the base of debris.
If the fuel lines seep fuel too long, loop a section of heater hose between them and clamp both ends tightly. If you have under 1/4 tank of fuel this may not be an issue.
If you look over your TPI setup carefully you will see how to preceed; bagging/labeling the bolts will greatly help on assembly. If you are new to this procedure a few digi pics taken along the way might be useful too.
Get an intake gasket set for your L98 from Auto Zone and have at it.
Instructor
Joined: Sep 1999
Posts: 197
Likes: 0
From: Ridgefield CT
Go to www.thirdgen.com and look under tech articles. There's an excellent writeup with pictures for the L98
Cruising
Joined: Feb 2004
Posts: 12
Likes: 0
From: Winfield Il
