COMPONENT LOCATION - SHEET 1 OF 2 - VEHICLES WITHOUT SELECTIVE CATALYST REDUCTION ( SCR ) SYSTEM
COMPONENT LOCATION - SHEET 2 OF 2 - VEHICLES WITH SELECTIVE CATALYST REDUCTION ( SCR ) SYSTEM
OVERVIEW
The exhaust system is manufactured from stainless steel and is attached to the underside of the vehicle body with rubber mountings which are located on hanger bars that are welded to the exhaust system. The rubber mountings locate on adjacent hanger brackets which are bolted or welded to the underside of the vehicle body and the subframes.
The exhaust system comprises three separate sections:
DESCRIPTION
FRONT SECTION
The front section has an inlet flange which mates with the turbocharger outlet. The flange is sealed with a stainless metallic gasket to the turbocharger and secured with a vee clamp onto the turbocharger housing.
An elbow from the flange is connected to the catalytic converter. The elbow contains a threaded boss for the installation of the Heated Oxygen Sensor (HO2S).
A support bracket with a stud is welded to the elbow. A mounting bracket is secured to the front section with a nut. The mounting bracket is connected to the top of the engine with three bolts, which secures the top of the front section to the engine. A band clamp is attached to the catalytic converter with a bolt to hold the front section in its position.
The catalytic converter is connected to a flange which mates with the flexible coupling of the center section.
CENTER SECTION - VEHICLES WITHOUT SELECTIVE CATALYST REDUCTION (SCR) SYSTEM
The center section is connected to the front section by a flange. It is sealed with a metal gasket and secured with three studs and nuts. The flange is connected to a flexible coupling with a pipe. The pipe comprises a threaded boss for the post-catalyst exhaust gas temperature sensor. A curved pipe from the flexible coupling is connected to the Diesel Particulate Filter (DPF).
A threaded boss is welded to the pipe and provides the connection of the differential pressure sensor high pressure pipe. A welded hanger bar with a rubber mounting is connected to a common bracket which in turn bolted to the front subframe, to support the center section.
The DPF outlet pipe comprises threaded bosses for the post-DPF exhaust gas temperature sensor and the differential pressure sensor low pressure pipe. An additional pipe is welded to the outlet pipe, which routes the exhaust gases from the outlet pipe to the Low Pressure (LP) Exhaust Gas Recirculation (EGR) valve. A welded hanger bar with a rubber mounting is connected to a common bracket which in turn bolted to the underside of the vehicle body, to support the center section.For additional information, refer to: (309-00C Exhaust System - INGENIUM I4 2.0L Diesel)
Diesel Particulate Filter (Description and Operation), Diesel Particulate Filter (Description and Operation).
CENTER SECTION - VEHICLES WITH SELECTIVE CATALYST REDUCTION (SCR) SYSTEM
The center section is connected to the front section by a flange. It is sealed with a metal gasket and secured with three studs and nuts. The flange is connected to a flexible coupling with a pipe. The pipe comprises a threaded boss for the post-catalyst exhaust gas temperature sensor. A curved pipe from the flexible coupling is connected to the DPF and Selective Catalyst Reduction (SCR) catalytic converter assembly. A threaded boss is welded to the pipe and provides the connection of the differential pressure sensor high pressure pipe. A welded boss provides the attachment of the Diesel Exhaust Fluid (DEF) injector. A mixer plate is located in the exhaust pipe downstream of the DEF injector. A welded hanger bar with a rubber mounting is connected to a common bracket which in turn bolted to the front subframe, to support the center section.
The SCR outlet pipe comprises threaded bosses for the post-DPF exhaust gas temperature sensor, the differential pressure sensor low pressure pipe and the post-SCR nitrogen oxide (NOx) sensor. An additional pipe is welded to the outlet pipe, which routes the exhaust gases from the outlet pipe to the Low Pressure (LP) Exhaust Gas Recirculation (EGR) valve. A welded hanger bar with a rubber mounting is connected to a common bracket which in turn bolted to the underside of the vehicle body, to support the center section.For additional information, refer to: Selective Catalyst Reduction (309-00C Exhaust System - INGENIUM I4 2.0L Diesel, Description and Operation).
REAR SECTION - VEHICLES WITH 5 SEATS
If the vehicle is equipped with 5 seats, the exhaust system rear section comprises a single rear silencer. The rear section is connected to the center section with a clamp. The rear silencer is connected by a pipe to the center section and secured with a clamp.
The rear section inlet pipe comprises a flexible coupling and a welded hanger bar. A hanger bar is attached to the hanger bracket with a rubber mounting. The hanger bracket is bolted to the underside of the vehicle body.
The rear section inlet pipe is routed in a central position under the vehicle, with a slight deviation around the Rear Drive Unit (RDU), where it joins with the rear silencer. The rear silencer is supported by three rubber mountings.
Two are attached to a hanger bracket bolted to the left side of the rear subframe and the third is attached to a hanger bracket on the right side of the rear subframe. The rear silencer has an outlet pipe at each end. Each outlet pipe is fitted with a stainless steel finisher.
REAR SECTION - VEHICLES WITH 7 SEATS
If the vehicle is equipped with 7 seats, the exhaust system rear section comprises two rear silencers. The rear section is connected to the center section with a clamp. The rear silencers are connected by two individual pipes to a 'Y' piece which the center section and secured with a clamp.
The rear section comprises a flexible coupling which is connected to the center section with a clamp. The flexible coupling outlet pipe is separated into two outlet pipes and a hanger bar and an exhaust brace are welded to the pipes to retain the system in position and reduce exhaust flexing. A hanger bar is attached to the hanger bracket with a rubber mounting. The hanger bracket is bolted to the underside of the vehicle body. The left rear silencer inlet pipe is connected to the rear section with a clamp. Inlet pipes to each rear silencer are routed with a slight deviation to each side of the RDU. Both inlet pipes have a welded hanger bar where it connects to the appropriate rear silencer. Rubber mountings and hanger brackets are attached to the hanger bars. The hanger brackets are bolted to the rear subframe on both side. Each rear silencer is connected to the rear armature via a welded hanger bar and rubber mounting. Each rear silencer has an outlet pipe at each end. Each pipe is fitted with a stainless steel finisher.
SYSTEM OPERATION
CATALYTIC CONVERTER
The oxidizing catalytic converter is fitted in the front section of the exhaust system, after the Heated Oxygen Sensor (HO2S). The catalytic converter assembly is common to vehicles with or without the DPF, however, the catalyst coating specification varies depending on the market. The HO2S monitors the exhaust gases leaving the engine. The engine management system uses this information to provide accurately metered quantities of fuel to the combustion chambers to ensure the most efficient use of fuel and to minimise the exhaust emissions.For additional information, refer to: Electronic Engine Controls (303-14C Electronic Engine Controls - GTDi 2.0L Petrol/GTDi 2.0L Petrol - SULEV, Description and Operation).
The catalytic converter further reduces the carbon monoxide and hydrocarbons content of the exhaust gases. In the catalytic converter the exhaust gases are passed through honeycombed ceramic elements coated with a special surface treatment called a 'washcoat'. The washcoat increases the surface area of the ceramic elements by a factor of approximately 7000.
On top of the washcoat is a coating containing platinum, which is the active constituent for converting harmful emissions into inert by-products. The platinum adds oxygen to the carbon monoxide and the hydrocarbons in the exhaust gases, to convert them into carbon dioxide and water respectively.
Exhaust - Ingenium i4 2.0l Diesel Diagnosis and Testing
PRINCIPLES OF OPERATION
For a detailed description of the Exhaust System, refer to the relevant Description and Operation section in the workshop manual. REFER to: Exhaust System (309-00C Exhaust System - INGENIUM I4 2.0L Diesel, Description and Operation).
INSPECTION AND VERIFICATION
CAUTION:
Diagnosis by substitution from a donor vehicle is NOT acceptable.
Substitution of control modules does not guarantee confirmation of a fault, and may also cause additional faults in the vehicle being tested and/or the donor vehicle.
NOTES:
For example, on the 2 volts range can measure 1mV or 2 K Ohm range can measure 1 Ohm. When testing resistance always take the resistance of the digital multimeter leads into account.
Visual Inspection
MECHANICAL
SYMPTOM CHART
SYMPTOM:
Exhaust excessively noisy
POSSIBLE CAUSES:
ACTION:
Rectify as necessary
SYMPTOM:
Engine performance reduced
POSSIBLE CAUSES:
ACTION:
DTC INDEX
For a list of Diagnostic Trouble Codes (DTCs) that could be logged on this vehicle, please refer to Section 100-00. REFER to: Diagnostic Trouble Code Index - INGENIUM I4 2.0L Diesel, DTC: Engine Control Module (ECM) B10A2-07 to P034B-76 (100-00 General Information, Description and Operation).