What does high HC ppm mean?

A high HC reading means the test found high HC (hydrocarbons) in your emissions. In other words, too much gas is left in the exhaust after combustion.

Can a bad o2 sensor cause high NOx?

High NOx emissions can occur when an engine’s air-fuel mixture is too lean. This could be caused by a problem with the vehicle’s oxygen sensor, malfunctioning air flow and coolant sensors or a leak in the fuel system.

How can I lower the emissions on my Diesel?

An excellent way to reduce diesel emissions is to install a selective catalytic reduction (SCR) onto your car. The job of the SCR is to convert gases from NoX to either nitrogen or water vapour. This advanced emissions control technology system adds ammonia to the exhaust gases.

Why are my car emissions so high?

The main culprit? A faulty exhaust. Usually, your exhaust and catalytic converter work together to limit the amount of harmful gasses your engine produces. However, when your exhaust is old, worn or damaged, it’s much less effective at doing so.

Will New spark plugs improve emissions?

A new set of plugs isn’t a cure-all for driveability and emissions problems, but in many cases a plug change can make a significant improvement. Changing the plugs can reduce hydrocarbon (HC) emissions up to several hundred parts per million, which may make the difference between failing and passing an emissions test.

Can a bad catalytic converter cause high idle?

A clogged converter can cause rough idle, engine hesitation upon acceleration, weakened power, hard-starting and, in some cases, a no-start condition. This symptom can be diagnosed by using a vacuum gauge on the intake manifold, or an exhaust back-pressure pressure gauge before and after the converter.

How do you fix NOx emissions?

The solution to this problem is called De-Carbonizing. It usually costs around two labor hours at a smog check repair station. It will remove a good amount of carbon out of an engine. This will increase combustion space, lower compression and lower NOx.

What does HC mean on a smog test?

High Hydrocarbon
High Hydrocarbon (HC) emissions are almost always a sign of poor fuel ignition. However, it’s not always that the engine’s ignition system is responsible for high Hydrocarbon emissions.