ClubWRX Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
498 Posts
Discussion Starter #1 (Edited)
What do you guys think might be the problem?

my thoughts were that after 79000 miles, an oxygen sensor went bad. also the spark plugs were never changed.

but, what else could possibly drop the mpg for a car that is driven slowly?
 

·
Registered
Joined
·
16,991 Posts
Plugs, clogged air filter, dirty fuel filter, carbon deposits (probably not), dirty injectors, PCV, low tire pressure...lots of things. :)
 

·
Registered
Joined
·
498 Posts
Discussion Starter #4
the air filter is very clean i checked that 2 days ago. could be the fuel filter, since thats still the original one. Tire pressure is fine, but what is the pcv?

and the outback engine is a 2.5 h4 like the impreza rs
 

·
Registered
Joined
·
475 Posts
PCV is an emissions valve that contains a check ball and sometimes fails to pressurize with wear. It is another one of these every 12k mile type replacements - usually like 2 bucks. It tends to be located as a vent in the valve covers on the other vehicles i've worked on. I'm not sure the exact location on your vehicle, but I am sure the manual will state what it is. Find it, and with the car on pull it and put your thumb over the end, it should pressurize, then turn the car off, and shake it, if it rattles and it pressurized then the pcv is in working condition.

para
 
1 - 6 of 6 Posts
Top