Genuine 1998 Jeep Wrangler Exhaust Manifold

1998 Jeep Wrangler Exhaust Manifold Parts Questions & Experts Answers

• Q: How to disconnect and replace the exhaust manifold and intake manifold on the 2.5L four-cylinder engine in a 1998 Jeep Wrangler?

  A: Disconnect the negative cable from the battery and drain the cooling system, disconnecting any coolant hoses that connect to the intake manifold. Remove the throttle body and label and disconnect any wiring, hoses, and control cables still connected to the intake manifold. Disconnect the bolt that retains the vacuum tubing bracket to the intake manifold, then reach around the back of the cylinder head to disconnect the multiple vacuum connector from the main assembly. Carefully lift the vacuum tube assembly from the engine compartment, unbolt the power steering pump if equipped, and set it aside without disconnecting the hoses. Disconnect the throttle valve linkage if equipped with an automatic transmission and disconnect the EGR tube from the intake manifold. Remove the intake manifold bolts, pull the manifold away from the engine slightly to disengage it from the dowel pins, and lift it from the engine. If the manifold sticks, tap it with a soft face hammer or a block of wood while supporting it. Thoroughly clean the mating surfaces, removing all traces of gasket material, and if replacing the manifold, transfer all fittings to the new one. Position the replacement gasket on the cylinder head and install the manifold, then install and tighten the intake manifold bolts in several stages, following the specified sequence. Reinstall the remaining parts in reverse order of removal, run the engine, and check for vacuum leaks and proper operation. For the exhaust manifold, remove the intake manifold, disconnect the EGR tube, and remove the two nuts and bolts that secure the exhaust pipe to the exhaust manifold, applying penetrating oil to the threads if necessary. Unplug the oxygen sensor wire connector if needed, remove the mounting nuts and spacers, and detach the exhaust manifold from the engine. Clean the mating surfaces and transfer the oxygen sensor to the new manifold if applicable. Reinstall the exhaust manifold and finger-tighten the nuts on the end studs, then reinstall the intake manifold and tighten all mounting fasteners to the specified torque, following the sequence shown. Reinstall the remaining components in reverse order of removal and run the engine to check for exhaust leaks.