Note. On the VAZ 2112 engine (1,5i) The oxygen concentration sensor is installed on the exhaust pipe of the muffler.
To carry out repair work, a viewing hole or overpass is required.
Removing
1. We prepare the car for repair work (see paragraphs 2b and 4 "Preparing the car for maintenance and repair").
2. Disconnect the wire connectors of the oxygen concentration sensor (see point 2 "Oxygen concentration sensor - check and replacement").
3. Using a 13 mm socket wrench, unscrew the two bolts of the movable hinge and remove the metal-graphite ring (see "Catalyst (catalytic converter) engine VAZ 2112 (1,5i) - removal and installation").
4. With a 13 mm socket wrench, unscrew the two nuts (1) fastening the exhaust manifold to the bracket and remove the bracket clamp.
5. We turn off two bolts of fastening of an arm of a reception pipe to the block of cylinders and we remove an arm (see points 6 and 7 "Engine muffler exhaust pipe 21124 (1,6i) - removal, installation, replacement").
6. Using a 14 mm socket wrench with an extension, unscrew six nuts (2) intake pipe to exhaust manifold (in photo item 4, three nuts from the side of the cylinder block are not visible) and remove the exhaust pipe muffler.
7. Remove the muffler intake pipe gasket from the exhaust manifold studs.
8. With a 22 mm open-end wrench, turn out the oxygen concentration sensor.
Installation
We install the exhaust pipe of the muffler and all removed parts on the car in the reverse order of removal. We replace the intake pipe gasket and fastening nuts with new ones. A bracket with damaged studs must also be replaced.
Recommendation. If one or more exhaust manifold studs are broken when removing the downpipe, remove the manifold (see "Exhaust manifold of the VAZ 2112 engine (1,5i) - removal and installation"). Drill out damaged studs (first with a drill with a diameter of 5, and then 8.5 mm) and cut the thread M10x1.25. Sometimes it is possible to turn out the remains of a broken hairpin with a tap. Screw repair studs (M10x1.25x25).