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emissions

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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
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
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...
Question
emissions test came back as not ready on 4 obd monitors
Here's the drive cycles for your vehicle. O2 and Catalyst monitor: Ambient temperature must be at 41 degrees or higher. Gas tank must be filled 1/2- 3/4's full. Start engine and let idle for 5 minutes with AC rear defogger...
Question
I have failed smog 2 times this past year (2016) for high NOx at low speeds but passed at higher speeds.
Hi there. The issue that you are having is the purge valve on the fuel system is not functioning correctly and needs check and possibly replaced. The code P0600 is referring that the dash is not communicating to the ECM...
Question
2006 Ridgeline RTL engine light stays on. Vehicle runs great and has new catalytic converter. Did reset but light came back on. Best guess please.
Hello, thank you for writing in. The checking engine light that you are receiving can stand for a large number of issues with the vehicle, and knowing what codes have been triggered are the only way to resolve the issue....
Question
I have a 2007 mdx and the check emission system light came on while I'm driving but not all the time. What can cause that issue?
For the transmission, check the fluid to see if it's low. If the fluid is low, then it will need to be topped off. If the fluid is full and is red in color, then there could be an issue...
Question
Check engine light is on. The gas cap is okay and the vent sensor by crankcase seems okay too. What could it be?
The issue could be the evaporative emission vent purge valve on the vapor charcoal canister. I recommend using a sniffer that is used for butane and check for a fuel leak around the vent purge valve and see if there...
Question
Catalytic Converter Replacement - 2001 Lexus IS300.
Hi there. Before you decide to have the catalytic converter replaced in your vehicle, consider performing the following checks: Check the following: A damaged or failed oxygen sensor The oxygen sensor wiring damaged or connected improperly The engine coolant...

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