Skip the auto shop - Our mechanics make house calls

Q: why wont my car pass smog

asked by on

put in new distributor, new plugs, cleaner in the the gas

My car has 186000 miles.
My car has an automatic transmission.

There are many components that work together to ensure your vehicle produces low emissions. It can be something as simple as a vacuum leak or faulty PCV valve, or even a faulty oxygen sensor or catalytic converter. If you didn’t pass the smog test, it is likely that your Check Engine Light is on, indicating a diagnostic trouble code that is stored. A certified technician, like one from YourMechanic, will be able to scan your vehicle and look at the data to determine the exact cause of your concern.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: 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...

Q: Cabin fan inop - no heat or A/C

While you have it turned on, try wiggling the wires to the resistor and blower motor to see if you have a poor wire connection. If it still will not come on again, then you may have burned out the...

Q: The emergency brake light on the dashboard wont turn off

The parking brake and fluid level is the only input to turn on the light but this system uses additional inputs from the ABS and traction control to input to microprocessor circuits that can turn on the indicator in the...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.