Genuine 1998 Jeep Wrangler Intake Manifold

1998 Jeep Wrangler Intake Manifold Parts Questions & Experts Answers

• Q: How to remove and install the lower intake manifold in 3.6L V6 engine on 1998 Jeep Wrangler?

  A: When replacing lower intake manifold, the fuel system pressure has to be discharged and the cable of the negative terminal of the battery has to be disconnected. If fitted, then under the pipe, there are few ballstuds which have to be pulled up with the help of hands to release the engine cover. Subsequently, eliminate the wiring harness to the MAP sensor and the throttle body, as well as the clamp to unfasten the intake duct from the throttle body; in addition to the PCV valve hose and the vapor purge hose and the brake booster hoses. The wiring harness retainers installed on the upper intake support bracket, one more retainer located on the stud bolt, nuts and the stud bolt need to be unbolted in order to take off the upper intake manifold bracket. Take off the nut on the bracket on the heater core return tube and the support bracket to upper manifold nuts, You only need to loosen the bolts not to fully take off the manifold before taking off the upper intake manifold. Remove the six upper and lower intake manifold gaskets and put caps to the intake ports to shield the motor from dust. If required, you can now take off the insulator of the left valve cover. Pop off the fuel injectors, and the fuel rail, pry the wiring harness retainer off the end of the manifold, unscrew the lower intake manifold bolts to tear the manifold away from the cylinder heads which will require getting rid of the six manifold-to-cylinder head gaskets. When installing, be sure that the surfaces of the cylinder heads, cylinder block and intake manifold are free of contamination and free of sealant/old gasket material, scraping off with a gasket scraper and thoroughly washing with a brake system cleaner. Reinstall the fuel injectors and install the fuel rail, following this, new intake manifold gaskets should be put on the manifold, the lower intake manifold should then be slowly put into position and the mounting bolts tightened only at this stage just enough to hold it in position. After tightening each of the mounting bolts in turn in accordance with the torque sequence, the upper intake manifold should be fitted, as prior to installation it is necessary to examine the condition of the rubber seals on each intake runner of the upper intake manifold and replace them if they are damaged. Last but not the least, replace the insulator to the mounting pins in case it was dismantled earlier.