That exhaust smell usually means the exhaust manifold needs to be replaced.
A leaking exhaust manifold is nothing to sneeze at. Not only can the exhaust fumes from combustion be toxic for you and your passengers, but a critical part of creating power inside an engine is properly channeling the exhaust gases out of the cylinder and away from the head. A leak in the manifold means that the tumbling of gases isn't optimized and can lead to potential or partial back pressure acting against the flow of exhaust. Besides the smell, you can check your exhaust manifold for leaks around the gaskets by holding your hand just above or below where the manifold meets the head and attempting to feel for a hot blowing breeze. Another sign of a problem will be elevated engine noise and poor acceleration. These aren't telling signs, however, so be sure you get confirmation by either a sniff test or by feeling for blow by. Don't leave a cracked manifold or leaking exhaust manifold gasket go unattended for too long. The headache you'll get from breathing in those fumes is bad enough, let alone the toll it takes on your power output and mileage loss.
Why exactly is the exhaust manifold so important?
The word "manifold" evolved from the Old English word "magnifeald" which means many folds. It refers to the way gases tumble through ports and passageways and converge into one output - the exhaust pipe. On many of today's smaller engines automakers will combine the exhaust manifold and catalytic converter into one assembly and the exhaust pipe will bolt right to it. Aftermarket steel tube exhaust manifolds are called headers and can typically handle exhaust gas pressure in a more efficient manner. This makes them ideal for racing and performance applications. Some modifications people can make to headers or exhaust manifolds will be ceramic coating or carbon graphite wrapping that keeps heat in the pipe and prevents it from radiating out into the engine compartment. This is ideal for power output, but can damage the manifold and gaskets in the long run.
Easy for some, and difficult for others.
Replacing an exhaust manifold is no easy task. Most of the time, your engine must come out of the engine bay in order to reach the exhaust manifold. In that case, it would be best to take it to a mechanic. If you have an older vehicle, or perhaps one with a large engine compartment, you may be able to reach the exhaust manifold(s) from underneath the car. The first thing you would have to do is remove any parts that may be connected to the manifold. Sometimes that can include O2 sensors, EGR pipes, vacuum tubing, etc. Once that is done, unbolt the rear of the manifold from the exhaust pipe. Now you can unbolt the exhaust manifold from the cylinder head. Scrape the leftover gasket off the cylinder head using alcohol or brake fluid with a plastic putty knife while making sure not to damage the surface. Then, set the new gasket in place and bolt the exhaust manifold in place. Hand-tighten at first. Next, bolt the exhaust pipe to the rear flange of the manifold. Again, hand-tighten only. You will have to make slight tweaks to the positioning of the manifold and pipe in order for both to line up properly. Once they are good to go, you can torque the bolts down. Finally, reconnect any parts you removed in order to access the old exhaust manifold, and you're done.
Your search for the best replacement parts ends here.
Don't waste your time buying a cheap exhaust manifold just to save some money. If you end up with bad parts, you may have to do the job again - and that's not fun. Just getting a quality exhaust manifold gasket can make the difference between an efficiently running engine and a clunker. At Car Parts Discount, we have the top brands in manifolds and gaskets for your exhaust system; all from the best original equipment and aftermarket manufacturers. So whether you need to replace your entire exhaust manifold and catalytic converter assembly or just simply the manifold gasket, we've got you covered.