How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Juan Crespo Your Own Question
Juan Crespo
Juan Crespo, Tech Trainer
Category: Subaru
Satisfied Customers: 1513
Experience:  A.S.E. Master Technician, Advanced Level, Emissions - Asian, Domestic, & European
19298667
Type Your Subaru Question Here...
Juan Crespo is online now
A new question is answered every 9 seconds

A recently bought subaru 2003 outback, the dealer said they

Customer Question

a recently bought subaru 2003 outback, the dealer said they had replaced the oxygen sensor, however the engine light is on code is p0170
I'm very worried
Submitted: 2 months ago.
Category: Subaru
Expert:  Eric replied 2 months ago.

HI,

Which engine is in yours - the 2.5 or 3.0L

Customer: replied 2 months ago.
its an xs, I think its a 2.5 but not sure
Expert:  Juan Crespo replied 2 months ago.

Hi there. Different expert here.

Data Trouble Codes (DTC) don't necessarily indicate a component is bad. In this particular case, the onboard computer has set P0170 because it is having difficulties setting fuel trim. Most of the times, replacing the Oxygen sensors doesn't cure this issue; instead, the fix is achieved by cleaning the mass air flow sensor (MAF) - just be sure to use the appropriate cleaner (click here for example).

Also, you might want to check that the air filter housing and hose to the throttle body are properly seated and not allowing unmetered air into the engine.