Water with black soot in exhaust

[srtblake]

the emission control on cars now is incredible. You are 10x more likely to die from carbon monoxide poisoning caused by a lawn mower or snow blower, than a car in a closed garage.

[Burrcold]

Originally Posted by KamalT

Thanks, load of my head

Better than a load on your head.

[arghx7]

A large amount (relatively speaking) of unburned HC passes through the exhaust during cold starts. This is because the catalytic converter hasn't started working efficiently yet. Also, direct injected gasoline engines have higher soot/particulate emissions than port injected, especially with side-mounted direct injection. The unburned HC and the soot/particulates are where the black stuff comes from.

If you have the right gas analyzer, you can see it in realtime readings of HC concentration (ppm) or mass flow or in accumulated modal/bag data.

[FRSFirestorm]

An example of just how much water be in an exhaust. A shot of my old hot rod launching at the strip. A complete custom dual exhaust but still running hi-flow cats. 10psi boost, methanol and nitrous.