Fig. 5.61. 1.6L Duratec Ti-VCT engine exhaust manifold: 1 – oxygen concentration control sensors; 2 – diagnostic oxygen concentration sensors.
Exhaust gases are removed from the engine through the exhaust manifold (an exhaust manifold combined with one or two neutralizers)…
…additional…
…and two main mufflers.
On vehicles with a 1.6L Duratec Ti-VCT engine, the catalytic converter includes two exhaust gas neutralizers; on vehicles with 2.0L and 2.3L Duratec-HE engines, there is one neutralizer.
On the exhaust manifold of the 1.6 l Duratec Ti-VCT engine, two control (main) sensors 1 (Fig. 5.61) of oxygen concentration and two diagnostic sensors 2 are installed.
On the catalytic converter of 2.0 and 2.3 l Duratec-HE engines, one control A and one diagnostic B oxygen concentration sensor are installed.
A metal-reinforced gasket is used to seal the connection between the flanges of the cylinder head and the exhaust manifold.
The inlet pipe of the additional muffler is connected to the exhaust manifold, and its outlet pipe is connected to the main mufflers. The connections of the inlet and intermediate pipes with the additional muffler, as well as the intermediate and exhaust pipes with the main mufflers are welded and therefore non-separable. The flange connection of the inlet pipe of the additional muffler and the exhaust manifold is sealed with a metal-reinforced gasket. Thus, all elements of the exhaust system located on the base of the body are made as a single unit and cannot be dismantled separately without the use of a metal-cutting tool. However, spare parts include individual elements of the system, which are connected by welding or special couplings during installation on the car.
The system elements are suspended from the body on five rubber cushions. Moreover, cushion A of the rear suspension of the exhaust pipe, cushion B of the suspension of the front part of the main muffler and three cushions B of the suspension of the catalytic collector and the rear part of the main muffler differ in shape.
To protect the engine and the body base from heating by the system elements, heat shields made of heat-resistant non-woven material are installed above the exhaust manifold, additional and main mufflers.
In addition, an additional steel heat shield is installed above the exhaust manifold.
The exhaust system does not require special maintenance. It is enough to periodically check the reliability of the tightening of the threaded connections and the integrity of the suspension cushions. In case of damage to the system elements, through corrosion or burnout, they are replaced as a whole, since the mufflers together with the pipes are non-separable units.
USEFUL TIP: Check the exhaust system periodically. If the exhaust system is noisy, check for leaks. To do this, start the engine and inspect the entire system. Run your hand over the possible leaks without touching the components, and you will immediately feel the gas leak. If necessary, replace rusted and burnt components.
If it is impossible to replace the defective unit with a new one, you can temporarily restore its functionality by applying a metal patch to the damaged area and securing it with clamps or wire. It is recommended to put a sheet of asbestos under the patch.
In addition, auto parts stores sell special kits for restoring exhaust system components, which can be used to temporarily repair damage to the system in order to get to a car service center or garage.
WARNING: Allow the exhaust system to cool before repairing it, as it becomes very hot during engine operation.
Exhaust gases are toxic, and poisoning occurs unnoticed, so be sure to open the garage door before starting the engine!