How to Remove the Fuel Injectors on a 1998 Buick Regal

The fuel injectors on the 1998 Buick Regal with the 3.8-Liter six cylinder are attached to the fuel rail and the intake manifold. The fuel rail routes around and over the intake manifold and is secured to the engine with four bolts. To remove any or all of the fuel injectors it is necessary to remove the plastic engine cover and fuel rail, as well as relieve fuel pressure.

Instructions

Removal

1

Lift the vehicle hood and support it with the hood prop rod. Disconnect the negative battery cable with a box end wrench. Allow the engine to cool completely before proceeding.

2

Turn the engine oil cap counterclockwise and remove it from the oil fill neck. Turn the oil fill neck counterclockwise one half turn and pull it out of the front valve cover. Gently pull up on the rear of the plastic engine cover to disengage the holding pin. Carefully pull up on each side of the plastic engine cover to disengage both center holding pins and remove the plastic cover from the engine. Some covers were installed with two bolts in the center instead of hold pins, if so equipped, remove these two bolts or damage will occur to the plastic cover. Install the oil cap and oil cap neck onto the valve cover to prevent any inner engine contamination.

3

Locate the schrader valve that is built into the fuel rail and remove the plastic cap. Install the fuel pressure tester onto the schrader valve and tighten the fitting with the wrench. Direct the fuel outlet hose from the pressure tester into the gas can. Slowly turn the manual valve on the test counterclockwise until fuel and pressure are dispensed into the gas can. When no more fuel is relieved, close the manual valve and remove the pressure tester. Replace the schrader valve cap.

4

Disconnect the fuel supply and return lines from the fuel rail with the fuel line quick disconnect tool. Cap the fuel supply and return lines with the 3/8-inch line caps. Remove the vacuum line from the fuel pressure regulator that is located on the front of the intake manifold just above the fuel rail. Disconnect the vacuum line from the throttle body if equipped.

5

Remove the three wire harness connectors from the ignition coil packs by lifting on the metal clip and pulling the harness away from the coil packs.

6

Remove the electrical connectors for each of the six fuel injectors by squeezing on the plastic retainer tab and pulling the harness out of the plug on each fuel injector. Remove the four fuel rail hold-down bolts with the socket and ratchet. Lift the fuel rail and fuel injectors off the engine using equal pulling force on each side of the fuel rail.

7

Remove the fuel injector retaining clip from the fuel injector with a flat-head screwdriver. Remove the fuel injector from the fuel rail.

Installation

8

Set up the new fuel injector in the following order: Install the new nylon injector collar over the lower part of the fuel injector. Install the brown O-ring to the lower part of the fuel injector. Install the black O-ring to the top of the fuel injector. Coat both O-rings with new engine oil.

9

Install the new fuel injector into the fuel rail and push the fuel injector retainer into place to secure the injector to the fuel rail. Replace all of the lower O-rings on the fuel injectors that were not replaced.

10

Set the fuel rail into position on the intake manifold. Gently apply pressure over each injector on the fuel rail to seat the fuel injectors into the intake manifold. Install the fuel rail hold-down bolts and tighten to 7 foot-pounds of torque with the torque wrench.

11

Install the wiring harness onto each fuel injector by pushing the connector into the plug until the plastic tab clicks.

12

Inspect the plastic fittings on the fuel lines for damage or cracks, and replace as necessary. Remove the line caps and install the fuel supply and return lines by clipping them into place on the fuel rail until the quick disconnect tabs click.

13

Slide the vacuum line onto the nipple on the fuel pressure regulator that is connected to the fuel rail. Install the coil pack wiring harnesses by setting them into their respective plugs and pushing on the metal clip until it latches into place.

14

Attach the negative battery cable and tighten the terminal with the wrench. Turn the ignition key to "on" for two seconds, then turn it off for 10 seconds. Turn the key back to "on" and inspect for any leaks around the injectors, fuel rail or fuel line quick disconnects. Turn the ignition off.

15

Remove the oil filler cap and neck from the front valve cover by rotating them counterclockwise and pulling them out of the valve cover. Set the plastic engine cover in place and tap the rear of the cover to engage the hold-down pin. Push down on the outside center of the engine cover to engage the center hold-down pins, or install the two hold-down bolts (if equipped). Set the oil filler neck in place and rotate one half turn clockwise to tighten it. Install the oil cap and shut the vehicle hood.