Q: Q: Car won't pass smog.

asked by on

My car will not pass smog. The codes that appear are for random misfires, a higher than normal idle, and bank 1 being too lean.

Hello! I will be happy to assist you. On your particular vehicle, random misfires are commonly caused by things such as low fuel pressure, a faulty oxygen sensor, bad vacuum lines, or faulty air flow sensors; a broken or loose vacuum line would be the most common of these for a turbo vehicle, such as your Jetta, since turbo vehicles use a lot more vacuum lines than those with normal engines. I suggest having a certified technician, such as one from YourMechanic, inspect your vehicle for the cause of the high idle condition, and possibly use a smoke machine to test the vacuum lines.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Q: Car won't pass smog.

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: P0010 -"A" Camshift Position Actuator Circuit/Open Bank 1 & OBD Bulb check failed on smog test - How to search for mechanic?

Hi there. The P0010 code is coming on for the VVT-I (variable valve timing with intelligence) system is malfunctioning. Changing the engine oil and filter could solve this issue and fix most of the problems. But if changing the engine...

Q: how to tell if timing chain is bad

Hello and thank you for contacting YourMechanic. Misfires can be caused by sloppy timing chain, spark plugs and wires not working, injectors not working, or a problem within the engine. To check the timing chain, get a timing light and...

Q: High idling, car jumps when put into gear

When the vehicle surges such as what you have described and has a high idle, they are generally related. A few different items can cause this fault such as the MAF sensor, a vacuum leak, a throttle body fault, or...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...