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4

Locally worse, globally better Diesel exhaust versus gasoline: about 15-20 % less CO2 about 4-100 times the NOx (highly temperature dependent, mitigated by proper use of diesel exhaust fluid, ref the VW scandal) and a fair amount of soot (esp. before common rail, mitigated by a particle filter). What this means for the local environment: Local CO2 is ...


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Because, as has been pointed out, the infernal combustion engine has dangerous byproducts - heat and poisonous gases, as well as noise - which need to be carried away from the persons using the vehicle. Society made a bad choice a century ago, and we live with the consequences to this day. Get an electric car and you won't have to replace your exhaust/...


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Take that airplane with the short, up-front, direct exhaust pipes. Start it up in your driveway early on a Saturday morning. See how popular you are with your neighbors.


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Adding to the excellent answers already given. An important point to note is that we need to have a catalytic converter somewhere in the exhaust a short exhaust will not have room to fit it. Then there are a host of other things car manufacturers determine while designing an exhaust system. For an engine to have optimum efficiency, the intake , ...


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The exhaust also creates a pressure differential, which can help scavenge exhaust gases from the chamber. So a properly tuned exhaust will therefore increase the fuel efficiency of the engine. Whilst an engine without an exhaust would make more power, it would also consume more fuel.


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Well, we can have a pipe going out the front of a car as in this design here: or its heavier predecessor: Arguably, the aerodynamic properties are not optimal in both, but here is a similar approach where aerodynamics have been considered for sure: other designs (like trucks) do account for aerodynamics by putting the exhaust tubing behind the relevant ...


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Safety, comfort, noise and space are the things that come to mind. Safety Exhaust gasses are hot as hell. Hot enough that we put heat shields all over the exhaust line. In engines, we are actively trying to remove heat. Adding more from the exhaust goes completely against that and would increase overheating. Also, would you want a hot exhaust pipe near ...


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Several things; Exhaust coming out the front is dangerous. If the fumes are ingested into the cab the driver may be harmed. Normally a car is driven forward. If the exhaust is coming out the back this gives the least chance of the fumes making it inside the cab. Mufflers are large components. Often there is not enough room inside the engine compartment to ...


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Before suspecting a bad O2 sensor... You need to be sure that the replacement MAF is suitable for your car. You mention the replacement MAF is a 5-pin and not a 4-pin like the one originally on the car. If the new sensor has a different flow-voltage calibration this would go a long way to explain what you are seeing. This is because the onboard fuel ...


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It sounds a lot to me like it could be your car's O2 (lambda) sensor in the exhaust. From wikipedia Oxygen sensor Function of a lambda probe Lambda probes are used to reduce vehicle emissions by ensuring that engines burn their fuel efficiently and cleanly Sensor failures Normally, the lifetime of an unheated sensor is about 30,000 to ...


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In answer to your last question, yes your car does have an o2 sensor, all modern cars do. Here are a few tips to pass an emissions test Drive the car on the freeway for at least 20 minutes before taking it in to get the emissions tested. If the engine is cool when you bring it in it won't burn as clean. Get a tune up. Replace the spark plugs, wires, and ...



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