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Throughout this group, references may be made to a particular vehicle by letter or number designation. A chart showing the breakdown of these designations is included in the Introduction Section at the front of this service manual.

EXHAUST SYSTEMS

The exhaust systems are produced in several configurations, depending on engine and car line (Fig. 1). One system has an underfloor catalytic converter, other systems require front mounted catalytic converters. Some turbocharged engines require, an underfloor converter/resonator assembly. Tail pipes,

mufflers, and resonators are sized and tuned to each vehicle/powertrain combination (Fig. 2).

EXHAUST BALL JOINT COUPLING

A exhaust ball joint coupling (Fig. 3) is used to secure the exhaust pipe to the engine manifold. This living joint actually moves back and forth as the engine moves, preventing breakage that could occur from the back-and-forth motion of a transverse mounted engine.

The exhaust ball joint consists of two bolts, two springs, and a ball joint seal ring which is a separate part from the exhaust pipe.

Fig. 2 Exhaust System Components

CATALYTIC CONVERTER

There is no regularly scheduled maintenance on any Chrysler catalytic converter. If damaged, the converter must be replaced.

Fig. 3 Ball Joint Connection

CAUTION: Due to exterior physical similarities of some catalytic converters with pipe assemblies, extreme care should be taken with replacement parts. There is internal converter differences required in some parts of the country (particularly California vehicles). The 2.2/2.5L engines equipped with a manual transmission will have an adaptor for a air injection tube.

HEAT SHIELDS

Heat shields (Fig. 4) are needed to protect both the car and the environment from the high temperatures

developed in the vicinity of the catalytic converters. 2.2/2.5L engines equipped with manual transmission where air is injected into the catalytic converter's, a heat shield is welded on the front converter.

Refer to Body and Sheet Metal, Group 23 for service procedures.

CAUTION: Avoid application of rust prevention compounds or undercoating materials to exhaust system floor pan heat shields on cars if equipped. Light overspray near the edges is permitted. Application of coating will greatly reduce the efficiency of the heat shields resulting in excessive floor pan temperatures and objectionable fumes.

The combustion reaction caused by the catalyst releases additional heat in the exhaust system. Causing temperature increases in the area of the reactor under severe operating conditions. Such conditions can exist when the engine misfires or otherwise does not operate at peak efficiency. Do not remove spark plug wires from plugs or by any other means short out cylinders if exhaust system is equipped with catalytic converter. Failure of the catalytic converter can occur due to temperature increases caused by unburned fuel passing through the converter.

The use of the catalysts also involves some nonautomotive problems. Unleaded gasoline must be used to avoid poisoning the catalyst core. Do not allow engine to operate above 1200 RPM in neutral for extended periods over 5 minutes. This condition may result in excessive exhaust system/floor pan temperatures because of no air movement under the vehicle.

EXHAUST GAS RECIRCULATION (EGR) SYSTEM

To assist in the control of oxides of nitrogen (NOx) in engine exhaust, some engines are equipped with an exhaust gas recirculation system. The use of exhaust gas to dilute incoming air/fuel mixtures lowers peak flame temperatures during combustion, thus limiting the formation of NOx.

Exhaust gases are taken from openings in the exhaust gas crossover passage in the intake manifold. REFER TO SECTION 25 EMISSION SYSTEMS FOR A COMPLETE DESCRIPTION, DIAGNOSIS AND SERVICE PROCEDURES ON THE EXHAUST GAS RECIRCULATION SYSTEM AND COMPONENTS.

Fig. 8 Front Tail Pipe Uni-Clamp

(2)Beginning at the ball joint, align and torque shoulder bolts (Fig. 3).

(3)Working from the front of system, align and clamp each component to maintain position and proper clearance with underbody parts (Fig. 10).

(4)Tighten all clamps and supports to the proper torques and clearances.

INTAKE AND EXHAUST MANIFOLDSÐTBI ENGINE

INTAKE MANIFOLD

Naturally Aspirated Die-cast aluminum longbranch fan design with remote plenum. The throttle body is installed on the upper plenum of the manifold.

Fig. 9 First Slip Joint Connection

EXHAUST MANIFOLD

All high strength iron casting that intermesh with the intake manifold. For standard engines a four branch design collects and directs exhaust gases to the conical (articulated joint connection) outlet.

THROTTLE BODY AIR HEATER

The throttle body air heater (Fig. 1) is attached to the exhaust manifold and is removable.

Inspect air heater connector tube; replace if damaged. Refer to Emission Control Systems Group 25,

Fig. 1 Air HeaterÐTBI Engine

INTAKE AND EXHAUST MANIFOLDS SERVICEÐTBI ENGINE

Intake and exhaust manifolds use a one piece gasket. Service procedures requiring removal and installation ( of either ) must include both manifolds.

FUEL SYSTEM PRESSURE RELEASE PROCEDURE

The Fuel System is under a constant pressure of at least 265 kPa (39 psi). Before servicing the fuel pump, fuel lines, fuel filter, throttle body or fuel injector, the fuel system pressure must be released.

(a)Loosen fuel filler cap to release fuel tank pres-

sure.

(b)Disconnect injector wiring harness from engine harness.

(c)Connect a jumper wire to ground terminal Number 1 of the injector harness (Fig. 2) to engine ground.

(d)Connect a jumper wire to the positive terminal Number 2 of the injector harness (Fig. 2) and touch the battery positive post for no longer than 5 seconds. This releases system pressure.

(e)Remove jumper wires.

(f)Continue fuel system service.

REMOVAL

(1) Perform fuel system pressure release procedure before attempting any repairs.

Fig. 2 Injector Harness Connector

(2)Disconnect negative battery cable. Drain cooling system. Refer to Cooling System, Group 7 for procedure.

(3)Remove air cleaner and disconnect all vacuum lines, electrical wiring and fuel lines from throttle body.

(4)Remove throttle linkage.

(5)Loosen power steering pump and remove belt.

(6)Remove power brake vacuum hose from intake manifold.

(7)Disconnect EGR tube from intake manifold and remove water hoses from water crossover.

(8)Raise vehicle and remove exhaust pipe from manifold.

(9)Remove power steering pump assembly and set aside.

(10)Remove intake manifold retaining screws (Fig.

3).

(11)Lower vehicle and remove intake manifold.

(12)Remove exhaust manifold retaining nuts (Fig.

3).

(13)Remove exhaust manifold.

Fig. 3 Intake and Exhaust Manifold Attaching

PointsÐ2.2/2.5L Engines

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CLEANING AND INSPECTION

(1)Discard gaskets and clean all gasket surfaces on both manifolds and on cylinder head.

(2)Test gasket surfaces of manifolds for flatness with a straight edge. Surfaces must be flat within 0.15mm per 300mm (.006 in. per foot) of manifold length.

(3)Inspect manifolds for cracks and distortion.

INSTALLATION

(1)Install a new intake and exhaust manifold gasket. Coat steel gasket lightly with Gasket Sealer on manifold side. Do not coat composition gasket with (any) sealer.

(2)Set exhaust manifold in place. Tighten retain-

ing nuts starting at center and progressing outward in both directions to 23 NIm (200 in. lbs.) torque. Repeat this procedure until all nuts are at specified torque.

EXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 7

(3)Set intake manifold in place.

(4)Raise vehicle and tighten retaining screws

starting at center and progressing outward in both directions to 23 NIm (200 in. lbs.) torque (Fig. 3). Repeat this procedure until all screws are at specified torque.

(5)Reverse removal procedures 1-9 for installation.

(6)With the DRB II use ASD Fuel System Test to pressurize system to check for leaks.

CAUTION: When using the ASD Fuel System Test, the Auto Shutdown (ASD) relay will remain energized for 7 minutes or until the ignition switch is turned to the OFF position, or Stop All Test is selected.