Correct exhaust manifold donut gasket?

Usually they go bad because your catalytic converter is clogged... So if there's any sign of it being blown out and not just rust and wear, you'll have the same problem again until you clean or replace the cat. I had to learn this the hard way and bought too many of these. And in my experience sometimes the super cheap ones were higher quality than the expensive ones, so if you can see it and inspect it in person, that'd be ideal. Of course the cheapest ones will be online and you just have to gamble on that. In general there's not much difference in price you pay.

 

The exhaust pipe gasket that goes between the exhaust manifold and the front exhaust pipe assembly is shown in catalog Figure 17-02, Exhaust Pipe, with part name code 17451, Toyota part number 17451-28040, sold in the U.S. as 17451-0D140. If you’d prefer a less-costly aftermarket part, RockAuto lists several substitutes.

The Repair Manual (more info) also says to measure the free length of the two compression springs using a vernier caliper. If either spring is shorter than 41.5 mm, replace it with a new one, part number 90501-35037, sold in the U.S. as 90501-A0005.