Let us spray. 1  When you're at the perfume counter, buying something smelly for your nearest and dearest this Christmas, just don't ask what's in it. 2  When you're at the perfume counter, buying something smelly for your nearest and dearest this Christmas, just don't ask what's in it. Hannah Betts argues you may get a nasty surprise.
Best Answer: When a catalytic converter goes bad it will restrict the flow of exhaust gases through the exhaust system. Basically, if the exhaust won't come out easily, air won't be taken into the engine easily to mix with the fuel to be burnt and give you power.
Before the catalytic converter, the oxygen sensor will zigzag up and down. To the contrary, the air-fuel sensor will be at a stable voltage. The post-cat oxygen sensor will be a straight line if the catalytic converter is good in most cases. If the catalytic converter is bad, the post-cat oxygen sensor will mirror the post-cat oxygen sensor.