What is a exhaust donut?
A puff of smoke that's in a shape of the exhaust pipe
A gasket/seal that is shaped like a donut. They are used between the manifold and the exhaust pipe.
Loosen two bolts on exhaust manifold and replace donut If it's an 8-valve, then it's probable that the exhaust header has burnt through where it transitions from vertical to horizontal just before connecting to the catalytic converter A new header collector can be fabricated in-place at some shops... check around.
All a donut gasket does is provide a seal between your exhaust and your manifold. If anything you may get better mileage because there is less restriction on your exhaust. The bad part is you may get some fumes in the passenger area. ==Another Answer== A bad donut gasket could in fact cause these symptoms. It will allow excess oxygen into the exhaust stream, tricking the oxygen sensor into thinking the engine is running lean…
The gasket between the exhaust manifold and the exhaust headpipe is often called a "donut". It's a specially designed composite gasket, that can endure the pressure and heat of the exhaust system. Measure the diameter of the headpipe, then you should be able to go to just about any auto parts retailer and request a gasket of that diameter. OReilly auto parts, Auto Zone, Pep Boys and any local auto parts retailer should be able…
Remove the three bolts between the exhaust manafold and the downpipe. Separate the connection and remove the old gasket. You may have to pull down (a little) on the downpipe to remove the old one. The install is the reverse order of these directions. It should take you about 30 minutes. Its a Very easy procedure.