2000 outback losing power going uphill also gets louder , starts fine runs and revs smooth in park. Check engine light is on code 420 (cat) last time uphill check engine light was flashing

Asked by TIMOTHYJMC Mar 12, 2019 at 09:29 PM about the 2000 Subaru Outback

Question type: Maintenance & Repair

7 Answers


Anytime u have a lack of power uphill and a flashing check engine light its fuel related.. 99% of the time its lack of fuel(failing pump)


Lack of power up a hill could be an ignition miss or a plugged up catalytic converter.


Clogged converters, dirty mass airflow sensor, and severe ignition coil problems are causes but its more likely to be fuel pressure problems when dealing with uphill problems


There is a code indicating the cat.


P0420 Cat inefficiency.. computer doesnt like the oxygen storage of the cat... has nothing to do with it being blocked


Get a chrap scantool that has live data graphing and look at the oxygen sensor voltage, go for a test drive. During a heavy acceleration or uphill drive monitor the voltage and see what it is.. if it drops lean near 0 volts its a fuel issue

Your Answer:


Looking for a Used Outback in your area?

CarGurus has 970 nationwide Outback listings starting at $3,900.

Postal Code:

Subaru Outback Experts

  • #1
  • #2
  • #3
View All

Find great deals from top-rated dealers


Related Models For Sale

Used Subaru Forester
34 Great Deals out of 1,048 listings starting at $2,555
Used Toyota RAV4
77 Great Deals out of 4,008 listings starting at $2,497
Used Honda CR-V
87 Great Deals out of 5,107 listings starting at $1,995
Used Subaru Legacy
12 Great Deals out of 429 listings starting at $1,499
Used Toyota 4Runner
10 Great Deals out of 370 listings starting at $5,900
Used Subaru Impreza
36 Great Deals out of 967 listings starting at $2,249
Used Toyota Tacoma
29 Great Deals out of 725 listings starting at $2,995
Used Toyota Highlander
51 Great Deals out of 1,806 listings starting at $3,499
Used Toyota Camry
53 Great Deals out of 1,897 listings starting at $1,888
Used Ford F-150
75 Great Deals out of 6,315 listings starting at $2,995

Used Cars for Sale

2021 Subaru Outback For Sale
128 listings starting at $32,044
2020 Subaru Outback For Sale
217 listings starting at $27,700
2019 Subaru Outback For Sale
6 Great Deals out of 74 listings starting at $25,531
2018 Subaru Outback For Sale
6 Great Deals out of 128 listings starting at $15,999
2017 Subaru Outback For Sale
161 listings starting at $13,999

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.