Toyota Celica/Supra 1971-1985 Repair Guide

Safety Precautions


For a number of reasons, exhaust system work can be the most dangerous type of work you can do on your car. Always observe the following precautions:

Support the car extra securely. Not only will you often be working directly under it, but you'll frequently be using a lot of force, such as heavy hammer blows, to dislodge rusted parts. This can cause a vehicle that's improperly supported to shift and possibly fall.
Wear goggles. Exhaust system parts are always rusty. Metal chips can be dislodged, even when you're only turning rusted bolts. Attempting to pry pipes apart with a chisel makes the chips fly even more frequently.
If you're using a cutting torch, keep it a great distance from either the fuel tank or lines. Stop what you're doing and feel the temperature of the fuel pipes on the tank frequently. Even slight heat can expand and/or vaporize fuel, resulting in accumulated vapor (or even a liquid leak) near your torch.
Watch where your hammer blows fall and make sure you hit squarely. You could easily tap a brake or fuel line when you hit an exhaust system part with a glancing blow. Inspect all lines and hoses in the area where you've been working.

Be very careful when working on or near the catalytic converter. External temperatures can reach 1,500°deg;F (816°deg;C) and more, causing severe burns. Removal or installation should be performed only on a cold exhaust system.

A number of special exhaust system tools can be rented from auto supply houses or local stores that rent special equipment. A common one is a tail pipe expander, designed to enable you to join pipes of identical diameter.

The exhaust system of Toyota Celica and Supra consists of several pieces. At the front of the vehicle, the first section of pipe connects the exhaust manifold to the catalytic converter. The in-line 6-cylinder uses a Y-pipe to connect the two outputs from the exhaust manifold. The catalytic converter is a sealed, non-serviceable unit which can be easily unbolted from the system and replaced if necessary.

The exhaust system is attached to the body by several hooks and flexible rubber hangers; these hangers absorb exhaust vibrations and isolate the system from the body of the car. A series of metal heat shields runs along the exhaust piping, protecting the underbody from excess heat.

When inspecting or replacing exhaust system parts, make sure there is adequate clearance from all points on the body to avoid possible overheating of the floorpan. Check the complete system for broken damaged, missing or poorly positioned parts. Rattles and vibrations in the exhaust system are usually caused by misalignment of parts. When aligning the system, leave all the nuts and bolts loose until everything is in its proper place, then tighten the hardware working from the front to the rear. Remember that what appears to be proper clearance during repair may change as the truck moves down the road. The motion of the engine, body and suspension must be considered when replacing parts.