unburned gas?

[kirbyy]

I was wondering if there was a way to tell if your car is not burning all the gas that goes thru the fuel injectors?

I say this because If I punch the car a bit..I can litreally see the gas guage go down..

[decke48]

with a 3 or 5 gas exhaust machine *aka the exhaust sniffer. you can see the HC output

[anothernord]

There will always be a little bit of unburned fuel, especially in Subarus, as the stock maps make the engine run rich anyway.

[99gtlimited]

most cars run rich to keep the combustion temps down, so a natural side-effect of this is an increase in unburnt HC's. If you were to lean the car out you would get more NOx emissions. The key to getting an "emissions friendly" vehicle is balancing the HC and NOx emissions so you don't get an excess amount of either and you want to get mostly C02 in the exhuast