Q: Spark Plugs Replacement cause P0170 and P0173?

asked by on April 17, 2017

Using yourmechanic.com, mechanic just replaced spark plug replacement on Wednesday (which went great btw!). 2 days later, Check Engine Light came up and I had OBDII Adapter handy that reads P0170 (Fuel Trim Bank 1) and P0173 (Fuel Trim Bank 2). I was wondering if this could be any related? What should I do next?

My car has 111000 miles.
My car has an automatic transmission.

Check Engine Light is on Inspection $94.99 - $114.99 Get a Quote

Hello, thank you for using our service and writing in. The fuel trim codes you are pulling are more likely to pertain to the ignition coil than the spark plugs. However these codes are also associated with the mass airflow sensor, and the oxygen sensor. All of which have powers in regulating the engine performance. At this point, you will want to run further tests on each of the components ruling them out one by one. You can use a voltmeter to test the resistance of each coil. The oxygen sensor can also be testing similarly, and the mass airflow sensor should be cleaned. For more help with this process, contact our service department to schedule another appointment.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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


Experienced Mechanic?

Earn up to $70/hr

What others are asking

What does the hill descent indicator mean?
The hill descent indicator is located on your instrument panel. This light illuminates when the hill descent feature is turned on.
Clutch pedal not engaging
Hello, you are correct that replacing the clutch master cylinder and slave is necessary as a pair. It would be helpful to know if it initially worked correctly after replacement. Since you have tried bleeding it, there is a chance...
fuel pump
It's hard to specify without knowing the exact model of your vehicle, but I will say that $300 for a timing belt and $300 for a fuel pump both sound very fair, but you may be trading low price for...
new stereo unit not working, interior lights and fuel level not working or showing up
Following the colors of the wires is not a full proof method to be sure you have made the correct connections. You clearly have some connections that are not correct. The only way to figure out what is what in...
Car won't start after starting minutes before, battery not dead
Firstly, remove the back seat's bottom. Then listen near the fuel pump access cover when someone cycles the key on and off. You should hear the fuel pump come on. If not then you may have a burned out fuel...
Won't start - P0410 and P1441 codes are on
Although it's very difficult to diagnose a problem like this without a complete inspection and downloading all error codes (https://www.yourmechanic.com/services/evaporation-vent-solenoid-replacement), at first glance, the P1441 EVAP issue may be the reason why you're engine isn't starting. When the EVAP solenoid...
What is the name of the liquid for the radiator?
The coolant this vehicle uses is called HOAT or Hybrid Organic Additive Technology. This coolant is supposed to be good for 5 years / 100,000 miles. If you are overheating then you will need to have the system tested by...
My car won't start it's just ticking. Tried to jump it and still wouldn't start. What else can it be?
Hello There, This is likely a problem with something on your starter called a starter solenoid. The starter solenoid is located on the starter and has internal electrical contacts that transmit electricity to the starter. As electricity is supplied to...
Car shakes in idle and
Hi there. A rough idling engine can be caused by a number of issues, some of them are serious while others tend to be minor, but the symptoms remain pretty much the same. The car will feel rough and bouncy...

Related articles

A Buyer’s Guide to the 2012 Mercedes-Benz CL-Class
Think Think of the 2012 Mercedes-Benz CL-Class as the two-door cousin of the S-Class lineup. Each vehicle in this class is a stylish, sexy coupe. What’s more – they all manage to combine incredible performance with svelte styling. They might...
P0173 OBD-II Trouble Code: Fuel Trim Malfunction (Bank 2)
P0173 P0173 code definition? P0173 Fuel Trim Malfunction (Bank 2) What the P0173 code means Code P0173 is triggered by the engine control module (ECM) when it detects that the air-fuel ratio is too lean or too rich. For most...
The Most and Least Expensive Cars to Insure
Car insurance quotes depend on the car make and model. The Honda Odyssey is the least expensive and the Dodge Viper is the most expensive to insure.