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emissions

Related articles

How to Replace an Evaporation Vent Solenoid
Emissions are regulated in part by the EVAP vent solenoid which goes bad when your car fails emissions testing or has extra pressure in the gas tank.
How to Replace a Secondary Air Injection Pump
A faulty secondary air injection pump can result in increased emissions, engine performance issues, and an illuminated Check Engine Light.
How to Replace an Evaporative Emission Control Canister
Emissions are regulated by the EVAP emission control canister which fails when the fuel tank gauge does not work or you fail an emissions test.
How to Replace a Canister Purge Solenoid
The canister purge solenoid prevents harmful vapor from releasing into the atmosphere. A faulty solenoid will not allow you to pass an emissions test.

Related questions

Question
Secondary air pump.
The air pump supplies the catalytic converter with extra oxygen so that it can efficiently catalyze any unburned fuel. On start up, the catalytic converter is cold and requires some help to quickly get up to temperature allowing it to...
Question
Will the P0597 code cause the car to fail emissions inspection in North Carolina?
Hi there. The code P0597 is for the thermostat heater control circuit. This means that the thermostat is electronically controlled in your vehicle. To see why this code is on, check the following: A loose or corroded connector on...
Question
I have a diesel car. Can I remove my muffler?
Hi there. Depending on your state that you live in and the emissions requirements, removing the muffler may cause your vehicle to fail emissions. Plus, on a newer vehicle that has a manufactures warranty, removing the muffler completely can void...
Question
I purchased a flood damaged car and replaced the engine and on the computer it's saying system running lean. What does that mean?
Hi there. When the computer says that the bank 1 or bank 2 is lean, it is referring that the cylinders do not have enough fuel to burn. Check the injectors and see if they are plugged up. Look for...
Question
I cannot locate the solenoid vent valve in my car.
Hi there. The purge control valve that you are looking for is located next to the valve cover and between the engine and the firewall to the front of the engine area. The valve should have vacuum type hoses attached...
Question
My car doesn't pass emissions because the catalyst system is below threshold, and the exhaust gas recirculalation is insufficient.
Hi there. The Engine Gas Recirculation (EGR) valve could be sticking or full of deposits from the exhaust system. Remove and clean the EGR valve before replacing it to see if the system will begin to operate. The oxygen sensors...
Question
Catalyst system Efficiency - P0420 - 2010 Ford Fusion.
Hello and thank you for contacting Your Mechanic. For the code P0420 to come on, there could be a lot of issues that could arise to a non functioning catalytic converter. Before you decide to replace the catalytic converter, consider...
Question
Car passed inspection but when I took it in I was told it never should have passed.
Hi there. Different people who check the emissions on a vehicle may only check the computer and the gas cap. They may not check under the vehicle for any signs of fuel leakage. That is probably why the vehicle passed....
Question
Why does my oxygen sensor heater stay in not ready mode on my 2002 Cadillac Escalade
Hello. If you have performed the necessary driver cycles and have not lost battery voltage or reset the computer at any time then you either have a problem with the heater circuit of the sensor or the computer is failing....
Question
Emissions light comes on and goes off.
Hi there. If the emissions light is coming on then going off, then the emission system could be picking up an evaporative leak. Check around the vehicle for any signs of fuel leaking and any fuel smell. Also, look at...
Question
Multiple problems with the car I just purchased
Hi there. I am so sorry that this has happened to you. The Check Engine Light bulb needs to be replaced so that you know when the system sees a problem; you didn't know that you would fail the emissions...
Question
Emissions lamp on and won't go out.
Hi there. There could be numerous different things wrong with the emission system to cause the light to stay on. The engine could be running rich or lean causing the O2 sensors to register the condition. The fuel system could...
Question
Why is my car failing CO levels at idle? It passes everything else with ease.
Hi and thanks for contacting YourMechanic. You may have to replace the distributor cap and rotor for a good, strong spark. Then, get some sea foam and put it in the vacuum system of the engine. This will clean the...
Question
What does it mean when there's black smoke coming from the exhaust?
Hi there. Black smoke from the exhaust is an indication of excessive fuel consumption. This may be the result of excessive fuel pressure, caused by a faulty fuel pressure regulator, a very dirty engine air filter, a faulty MAF (mass...
Question
Check Engine Light is on - 2007 Toyota Sienna
This code relates to a heated oxygen sensor which is a unit inside your exhaust system that reads exhaust gases and relays this information to the car's computer. The computer uses this information to make adjustments to fueling. This sensor...
Question
Fuel gauge keeps jumping back past the E on the gas reader
Hey, thanks for writing in. There may be two different issues at play here. Your fuel gauge sending unit may be faulty which is what causes the fuel gauge to fluctuate erratically not reading correctly. This is a small...
Question
Would a major leak from my exhaust back box cause it to fail the emmisions test and LAMDA reading
Hello - while an exhaust leak can have a minor effect on emissions, I would not expect that to cause a "Fail" - UNLESS your state or metro area does tolerate an exhaust leak for safety reasons (carbon monoxide poisoning...
Question
Things to do when getting smog test at Star station
Hi there. The smog test for vehicles of 1996 and newer will pass if the engine light is off and the gas cap passes the sealed test. As long as the gas cap is sealing to the fuel inlet tube...
Question
A.I.R. pump is missing in my car
Hello. The A.I.R. system is an emissions system that is designed to inject air into the exhaust manifold to help with the combustion of any unburned fuel before it reaches the catalytic converter, resulting in cleaner emissions. In order to...
Question
How does a smog test work?
How a smog test works depends on where you live. If you live in the United States different states have different requirements and some parts of states may have as well. Usually the more densely populated areas require more stringent...

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