Toyota 25051-28340
Exhaust Manifold

The first step in catalytic converter removal from the 2AZ-FE emission control system is to remove the No. 1 engine under cover. Initiate removal of the No. 1 exhaust manifold insulator while then proceeding to extract the air fuel ratio sensor. Next detach the heated oxygen sensor connector before removing the front exhaust pipe assembly through the process of unfastening 4 bolts as well as 2 compression springs. The exhaust manifold converter sub-assembly requires removal through bolt and nut extraction of the manifold stay followed by removing the bolt and nut from the No. 2 manifold stay. Following nut removal the exhaust manifold converter sub-assembly separates from the exhaust pipe while the removal of 4 bolts enables taking off the No. 1 exhaust manifold converter heat insulator leading to No. 2 exhaust manifold heat insulator removal by unbolting its 2 nuts.

The first step to remove the catalytic converter from the 2AZ-FE emission control system begins by taking off the No. 1 engine under cover. The following step requires removing the No. 1 exhaust manifold insulator. The air fuel ratio sensor needs to be uninstalled as the next step. First disconnect the heated oxygen sensor connector followed by the removal of four bolts together with two compression springs to separate the front exhaust pipe assembly. The exhaust manifold converter sub-assembly requires the removal of its bolt and nut combination to separate the manifold stay before proceeding with the removal of the bolt and nut combination for the No. 2 manifold stay. Deattach the exhaust manifold converter sub-assembly by first exposing the 5 nuts then hand them off after loosening them followed by detaching the front exhaust pipe assembly with the 4 bolts and 2 compression springs. Last step involves removing 2 bolts to detach the No. 2 exhaust manifold heat insulator.

Install the No. 2 exhaust manifold heat insulator first using 2 bolts that should attain 12 Nm (122 kgf-cm, 9 ft-lbf) of torque. After mounding the 4 bolts of the No. 1 manifold converter insulator it should be torqued to 12 Nm (122 kgf-cm, 9 ft-lbf). The exhaust manifold installation requires the use of new gaskets for nuts which must be tightened in the given sequence with a torquing value of 37 Nm (377 kgf-cm, 27 ft-lbf). After bolting the manifold stay using a nut and torquing it to 44 Nm (449 kgf-cm, 33 ft-lbf) you must install the No. 2 manifold stay using the same bolt and nut procedure and torquing force of 44 Nm (449 kgf-cm, 33 ft-lbf). Mount the front exhaust pipe by applying 4 bolts and installing two required compression springs. The procedure begins with sensor installation for the air fuel ratio followed by application of the No. 1 exhaust manifold insulator followed by exhaust gas leak inspection before the No. 1 engine under cover installation.

Install the No. 2 exhaust manifold heat insulator using 2 bolts, torqued to 12 Nm (122 kgf-cm, 9 ft-lbf).

Install the No. 2 manifold stay with a bolt and nut, also torqued to 44 Nm (449 kgf-cm, 33 ft-lbf).

Take out the 4 bolts and 2 compression springs.