The various chemicals emitted in exhaust gasses from an internal combustion engine. The usual gasses which are measured through emissions testing are Nitrogen Oxide (NO2), Carbon Monoxide (CO2), and HydroCarbons (HC).

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What does a water like drop coming out of the exhaust of the car signify?

Sometimes while driving in the traffic, I come across a car or two which would be dripping water-like drop from it's exhaust steadily in a break of 4-5 seconds. I tried to ask a couple of people at ...
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1answer
83 views

Difference between fuel injectors and emissions standards

I have a 2004 Honda Accord EX Sedan with a 2.4L I-4 with California emissions and 250k miles on it. I desperately need to replace my fuel injectors but the price is steep! Can someone explain to me ...
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1answer
111 views

Evaporator canister purge system advice needed

1995 Blazer - 4.3 L Vortec V6 CMFI (vin W w/ PCM) 230,000 miles There are no trouble codes. This is a OBD-I or 1.5 system from a GM transitional year (I have the OBD-II style connector). I have ...
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7answers
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What is the point of the exhaust?

I was thinking today, what is the actual point of an exhaust? Why can't we just have a pipe going out the front of a car instead of taking all the gases to the back of the car? I can only see ...
8
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1answer
62 views

What is the “Activated Carbon Cannister”?

Why do I have an "Activated Carbon Cannister" in my unleaded/petrol car? What is it's purpose? How does it work? Do I need to do anything to maintain it? I would like a general answer, but my car ...
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444 views

Why don't all diesel engines have throttle plates?

I learned recently that many older and some newer diesels don't have throttle plates to control airflow. I was also quite shocked to learn about a condition called diesel engine runaway. Apparently ...
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1answer
2k views

How to determine if P0430 is O2 or catalytic converter

2009 CTS4 3.6L P0430 catalyst below efficiency bank 2 comes on periodically. (There are no other codes being thrown.) I put a data logger on it today on my drive to work and the rear sensor is ...