03 subaru legacy engine trouble

Asked by Mar 28, 2016 at 06:37 PM about the 2003 Subaru Legacy 2.5 L

Question type: Maintenance & Repair

2003 subaru legacy l wagon 2.5

Misfiring, backfiring, loss of power, engine vibration, stalling, now wont move. I have po301,
302, 420, and 457 codes.

Replaced plugs, wires, fuel filter, upstream o2 sensor, and crank sensor. Im out of ideas and
money. I need to know what this issue is soon or I may just drive the thing off a cliff and never
look back. at my wits end. Please help.

2 Answers

37,965

The po302 was a miss fire on cylinder #2, P0420 SUBARU - Catalyst System Efficiency Below Threshold... Possible causes... - Three way catalyst converter Bank 1 - Exhaust tube - Intake air leaks - Fuel injectors may be faulty - Fuel injector leaks - Spark plugs may be faulty - Improper ignition timing - Engine Control Module (ECM)... Some Tech notes.... As the code description implies the P0420 code means that the vehicle's control module has detected that the three-way catalytic converter is not working properly (is not as efficient as the factory is expecting). Replacing the oxygen (O2) sensors may sometimes fix the code, but in most cases the catalytic convert needs to be replaced to fix the problem. If the P0420 code is combined with other codes, try fixing the other codes first.... P0457 SUBARU - EVAP System Leak Detected Fuel Cap Loose/Off... Possible causes.... - Missing fuel filler cap - Incorrect fuel filler cap used - Fuel filler cap remains open or fails to close - Foreign matter caught in fuel filler cap... EVAP control system has a very large leak such as fuel filler cap fell off Possible symptoms... - Engine Light ON (or Service Engine Soon Warning Light) - Possible a noticeable fuel odor caused by the release of fuel vapors.... P0457 Subaru Description.... This diagnosis detects leaks in the Evaporative Emission System (EVAP) purge line using engine intake manifold vacuum. If pressure does not increase, the Engine Control Module (ECM) will check for leaks in the line between the fuel tank and EVAP canister purge volume control solenoid valve under the following vacuum test condition... The vacuum cut valve bypass valve is opened to clear the line between the fuel tank and the EVAP canister purge volume control solenoid valve. The EVAP canister vent control valve will then be closed to shut the EVAP purge line off. The EVAP canister purge volume control solenoid valve is opened to depressurize the EVAP purge line using intake manifold vacuum. After this depressurization is implemented, the EVAP canister purge volume control solenoid valve will be closed.

2,810

You need an ignition coil. $40 on eBay. Keep it simple.

1 out of 1 people think this is helpful.

Your Answer

Add photo

Related Questions

  • 99 Subaru Legacy outback overheating ONLY when driving 31 answers

    My 99 Subaru Legacy has only 66,000 miles on it. Last week while driving it started to overheat. the coolant was low so I filled it up. Ran fine for 10 minutes, then started to overheat again. It d...

    1999 Subaru Legacy

    -

    Maintenance & Repair

  • Subaru Legacy 2001 bad acceleration 38 answers

    Well i have subaru legacy 2001, My problem is when shift the 1 or 2 Gear and then press the accelerator the acceleration RPM slowly slowly increase when it reach to above 1500 RPM then take pickup f...

    2001 Subaru Legacy GT

    -

    Maintenance & Repair

  • 1996 Subaru legacy L drive train 6 answers

    My Subaru legacy L, when turning I feel the rear tires like trying to turn and throw gravel, and when I put it in park, it kinda slam's.. very worried, any suggestions

    1996 Subaru Legacy 4 Dr L Sedan

    -

    Maintenance & Repair

  • '98 Legacy L Spitting and sputtering 5 answers

    I own a 98 Legacy L, 2.2L engine. i was driving recently and had the car start to spit and sputter no matter if i backed off the gas or pushed the peddle to the floor. I sucked down a quarter tank of ...

    1998 Subaru Legacy 4 Dr L AWD Wagon

    -

    Maintenance & Repair

  • How long do Subaru Legacys last? 57 answers

    What is a typical lifespan for Subaru Legacy wagons? I have a 1996 Subaru Legacy Brighton with 132,000 miles (bought it used, with 18k already on it). I've kept it maintained over the years. Two di...

    1996 Subaru Legacy 4 Dr Brighton AWD Wagon

    -

    General

Search Subaru Legacy Questions

Subaru Legacy Experts

#1 Anthony_60
Anthony_60
Reputation 1,020
#2 Nick Eidemiller
Nick Eidemiller
Reputation 680
#3 dandyoun
dandyoun
Reputation 600
View All

Related Models For Sale

Used Subaru Impreza
206 Great Deals out of 7,573 listings starting at $1,795
Used Subaru Outback
392 Great Deals out of 30,027 listings starting at $1,500
Used Subaru Forester
341 Great Deals out of 20,144 listings starting at $1,290
Used Subaru Impreza WRX
44 Great Deals out of 1,253 listings starting at $1,999
Used Honda Accord
1,187 Great Deals out of 77,640 listings starting at $969
Used Subaru Impreza WRX STi
34 Great Deals out of 640 listings starting at $8,500
Used Toyota Camry
1,457 Great Deals out of 100,042 listings starting at $700
Used Honda Civic
1,139 Great Deals out of 65,603 listings starting at $1,500
Used BMW 3 Series
1,752 Great Deals out of 40,930 listings starting at $1,250
Used Mazda MAZDA6
219 Great Deals out of 14,458 listings starting at $1,995
Used Audi A4
343 Great Deals out of 13,166 listings starting at $1,599
Used Honda CR-V
1,256 Great Deals out of 73,997 listings starting at $1,650
Used Acura TL
329 Great Deals out of 7,131 listings starting at $2,000

Used Cars For Sale

2017 Subaru Legacy For Sale
11,030 listings starting at $20,369
2016 Subaru Legacy For Sale
22 Great Deals out of 897 listings starting at $17,968
2015 Subaru Legacy For Sale
32 Great Deals out of 792 listings starting at $10,995
2014 Subaru Legacy For Sale
51 Great Deals out of 1,095 listings starting at $9,990
2013 Subaru Legacy For Sale
36 Great Deals out of 731 listings starting at $7,995