Skip the auto shop - Our mechanics make house calls

Q: smog test incomplete.

asked by on

OBD catalyst/oxy snsr heat not completed. no engine check light on.

My car has 60000 miles.
My car has an automatic transmission.

If your Check Engine Light is not illuminated, there is not a fault with the system. Before a vehicle can pass emissions testing, certain readiness monitors must be completed. One of which is the heater O2 monitor. The vehicle will need a cold start full drive cycle completed to get that monitor to set.

Let the vehicle completely cool down overnight. The next morning start the vehicle and let it warm up and take it on a drive. Head towards the interstate. Merge into the interstate and get into the slow lane of traffic. Hold the throttle to where your speed is between 55-65 mph. Do this for 3 minutes. Then get off at the next exit and try to time your exit to where your vehicle can coast down to 30 mph without touching the brakes during exiting. USE CAUTION AND AVOID COLLISIONS. BRAKE IF YOU MUST. The point of this is to force readiness. Circle back around and get back in the interstate in the opposite direction and head back home. Once home, let the vehicle cool back down. A few hours should be plenty of time.

Start the vehicle, if the Check Engine Light is not illuminated, you should be ready for inspection. If the Check Engine Light is on, you will need a qualified technician, like one from YourMechanic, to determine what the fault is and which part will need replacement.

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!
  1. Home
  2. Questions
  3. smog test incomplete.

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: New battery goes dead overnight

If you have a new battery, you should be able to drive for a few hours and be able to restart the car a couple of dozen times even if the alternator is not working. So I suspect you have...

Q: Heater will not stay hot

Hello. You are likely facing multiple issues at once. The low coolant would absolutely cause the heater to function intermittently. If you are continuously losing coolant there is likely a leak on the system and it will need to be...

Q: Took for smog test and fail said that it was supposed to be 430 but was 469. What do I do to fix it?

Generally, when the car fails a smog test, the smog shop will give you a print out and tell you what specifically caused the failure. Some common causes for failing these tests are faulty O2 sensors, bad catalytic converters, vacuum...

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...
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...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.