What causes HC to be high in emissions?
Ignition defects including dirty spark plugs, leaking or open-circuited spark plugs or wires, or defective ignition coils can all result in a shortage of spark energy. Any shortage of spark energy may cause high HC emissions. If the spark occurs at the wrong time, incomplete combustion and high hydrocarbons may result.
How can I lower my HC emissions?
On a precomputer carbureted car, one way to get under the HC and CO limits is to retard the ignition timing. This will slow the idle and provide a longer, hotter burn. Then, bring the idle speed back up to specs with the throttle stop screw or idle stop solenoid, which will admit more air.
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.
What causes a failed emissions test?
One reason for a failed emissions test is an overdue oil change. Your vehicle’s manual should tell you how often you need to change your oil, and skipping these important milestones can result in failing marks during an emissions test. Dirty oil in the crankcase could release additional pollutants, reports Edmunds.com.
How do you fix high exhaust emissions?
But there are things you can take into account to improve your driving and ways to maintain your car to ensure you are reducing your car’s emissions as much as possible….
- Use a cleaning agent.
- Use better fuel.
- Change the oil.
- Change the air filter.
- Check your tyre pressure.
- Air conditioning system.
- Reduce idle time.
Can spark plugs affect emissions?
Change your spark plugs and check your spark plug wires: Worn or fouled spark plugs, as well as worn spark plug wires can result in less-than-stellar results on your emissions test. And it’s the only spark plug recognized by the EPA (Environmental Protection Agency) as an emissions control device.
How do you pass an emissions test with 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.
How can I get my car to pass emissions?
How to reduce your car’s emissions (and pass the NCT in the…
- Repair the exhaust. Inspect your exhaust and repair any holes that you see.
- Get a service.
- Fuel additives.
- Use better quality fuel.
- Inflate tyres.
- Before the test.
What causes a high HC reading on an emissions test?
Let’s start by understanding what things cause a high HC reading. 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.
What happens if you fail the emissions test?
Think of failing the emissions test as a positive experience rather then a negative one. Where you may have not noticed your vehicle is or was not performing at it’s best and wasting fuel, failing the emissions test will identify this condition and allow you to fix the problem. You will absolutely save money on the long run.
What to do if your car fails the HC test?
Check cracks in the air duct from the air filter box to the throttle body. If you can’t find any, spray carburetor cleaner around the intake manifold while watching the O2 sensor readings on your scan tool. In many cases you can see the vacuum leak as it sucks in the liquid spray.
What happens when you fail the HC ppm test?
Interpret the HC PPM reading. If you fail the HC PPM part of the test, it could mean that there is a problem with the carburetor, fuel injection system or oxygen sensor, or that the engine oil is diluted or the air cleaner is dirty.