The 2004 Impreza 2.5L is a solid AWD platform undermined by one catastrophic flaw: head gasket failure. Beyond that, expect typical Subaru transmission mount wear and the occasional speed control cable issue, but the head gasket defines ownership of this generation.
Head Gasket Failure (External Coolant Leaks)
Common · high severity
Typical onset: 80,000-120,000 mi
Symptoms: White crusty residue on engine block near head seam, Sweet coolant smell after driving, Gradual coolant loss without visible puddles, Overheating if neglected long enough
Fix: Both head gaskets replacement is mandatory even if only one side leaks currently. Requires engine removal or lifting for proper access. Machine shop resurface heads if warped. 12-16 labor hours plus machine work. Replace timing belt, water pump, and all coolant hoses while you're in there or you're a fool.
Estimated cost: $2,200-3,500
Internal Head Gasket Failure (Combustion Gas into Coolant)
Occasional · high severity
Typical onset: 100,000-150,000 mi
Symptoms: Bubbling overflow tank even when cold, Exhaust gas smell from radiator cap, Mysterious coolant consumption with no external leaks, White smoke from exhaust (if severe), Positive combustion gas test
Fix: Same head gasket job as external leak but urgency is higher—combustion pressure cooks coolant and can crack heads. Heads must be pressure-tested and often need surfacing or replacement. 14-18 hours labor. If you drove it overheated, budget for head replacement not just resurface.
Estimated cost: $2,800-5,000
Transmission Mount Collapse
Common · low severity
Typical onset: 70,000-110,000 mi
Symptoms: Clunk when shifting from reverse to drive, Excessive engine movement visible from engine bay during throttle blip, Vibration at idle in gear, Notchy shifter feel in manual transmission cars
Fix: Rear transmission mount (pitch stopper) turns to mush. Simple bolt-in replacement. 1.0-1.5 hours. OEM Subaru part strongly recommended over aftermarket—cheap mounts fail in 20k miles.
Estimated cost: $150-280
Front Lower Control Arm Bushing Failure
Common · medium severity
Typical onset: 90,000-130,000 mi
Symptoms: Clunking over bumps from front suspension, Wandering steering or pull to one side, Inner front tire wear, Visible cracks or torn rubber in control arm bushings
Fix: Front lower control arm bushings rot out. Most shops replace entire control arms rather than press bushings—easier and not much more expensive. Alignment mandatory after. 2.5-3.5 hours labor per side, usually do both.
Estimated cost: $450-750
Cruise Control Cable Detachment/Fraying
Occasional · low severity
Symptoms: Cruise control inoperative, Throttle sticking open momentarily (rare but dangerous), Visible fraying at throttle body or under hood
Fix: Speed control cable can fray or detach at throttle body. Inspect during oil changes. Replacement is straightforward cable swap. 1.0-1.5 hours. NHTSA had a recall but many cars missed it—check VIN for open campaigns.
Estimated cost: $180-320
Transmission Oil Cooler Line Corrosion (Automatic)
Occasional · medium severity
Typical onset: 100,000+ mi or salt-belt cars earlier
Symptoms: Red ATF fluid dripping near radiator, Low transmission fluid level, Transmission slipping or delayed engagement if fluid level drops critically
Fix: Steel ATF cooler lines rust through on salt-belt cars. Replace lines, refill and flush transmission fluid. 2.0-3.0 hours. Catch it early or you're buying a transmission.
Estimated cost: $350-600
Owner tips
Use Subaru OEM coolant conditioner additive at every coolant change—it buys you maybe 20k more miles before head gasket failure
Check coolant level monthly and look for crusty white residue on engine block near head seams—early detection saves thousands
Do timing belt, water pump, and all idler pulleys at 100k mi regardless of condition; you'll have it apart for head gaskets soon anyway
Great AWD platform if you budget $3k for inevitable head gaskets or find one already done with receipts—otherwise it's a ticking time bomb that will strand you.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.
Be the first to unlock repairs for the 2004 Subaru Impreza
Procedures haven't been generated for this vehicle yet. Become the founding sponsor and we'll generate expert-grade, step-by-step repair walkthroughs for every common job on it — free for every mechanic and DIYer who looks it up after, forever.
AIR BAGS:FRONTAL:PASSENGER SIDE:INFLATOR MODULE · 23V076000
2023-02-13
Subaru of America, Inc. (Subaru) is recalling certain 2004-2005 Impreza and WRX vehicles that received replacement front passenger air bag inflators under a previous recall. The replacement air bag inflators may have been installed incorrectly.
Consequence: An incorrectly installed inflator may not properly inflate the passenger air bag, increasing the risk of injury during a crash.
Remedy: Dealers will inspect the passenger inflator and if necessary, install a new inflator kit, free of charge. Owner notification letters are expected to be mailed April 14, 2023. Owners may contact Subaru's customer service at 1-844-373-6614. Subaru's number for this recall is WRF-23.
AIR BAGS:FRONTAL:PASSENGER SIDE:INFLATOR MODULE · 20V001000
2020-01-02 · EA15001
Subaru of America, Inc. (Subaru) is recalling certain 2009-2013 Forester, 2003-2006 Baja, 2004-2011 Impreza, 2004-2014 WRX (STI included), 2003-2014 Legacy and Outback, and 2005-2006 Saab 9-2X vehicles originally sold, or ever registered, in the states of Alabama, California, Florida, Georgia, Hawaii, Louisiana, Mississippi, South Carolina, Texas, Puerto Rico, American Samoa, Guam, the Northern Mariana Islands (Saipan), and the U.S. Virgin Islands or "Zone A."
These vehicles had their passenger frontal air bag inflators previously replaced under a prior recall using inflators of the same design. The inflators may explode due to propellant degradation occurring after long-term exposure to high absolute humidity, temperature and temperature cycling.
Consequence: An inflator explosion may result in sharp metal fragments striking the driver or other occupants resulting in serious injury or death.
Remedy: Subaru will notify their owners. General Motors will notify Saab owners. Dealers will replace the passenger air bag inflators with alternate inflators, free of charge. The recall began January 7, 2020. Subaru Owners may contact Subaru customer service at 1-844-373-6614. Saab owners may contact the Saab Customer Assistance Center at 1-800-955-9007. Subaru's number for this recall is TKA-20.
AIR BAGS:FRONTAL:PASSENGER SIDE:INFLATOR MODULE · 20V002000
2020-01-02 · EA15001
Subaru of America, Inc. (Subaru) is recalling certain 2009-2013 Forester, 2003-2006 Baja, 2004-2011 Impreza, 2004-2014 WRX (including STI), 2003-2014 Legacy and Outback, and 2006 Saab 9-2X vehicles originally sold, or ever registered, in the states of Arizona, Arkansas, Delaware, District of Columbia, Illinois, Indiana, Kansas, Kentucky, Maryland, Missouri, Nebraska, Nevada, New Jersey, New Mexico, North Carolina, Ohio, Oklahoma, Pennsylvania, Tennessee, Virginia, and West Virginia or "Zone B."
These vehicles had their passenger frontal air bag inflators previously replaced under a prior recall using inflators of the same design. The inflators may explode due to propellant degradation occurring after long-term exposure to high absolute humidity, temperature and temperature cycling.
Consequence: An inflator explosion may result in sharp metal fragments striking the driver or other occupants resulting in serious injury or death.
Remedy: Subaru will notify their owners. General Motors will notify Saab owners. Dealers will replace the passenger air bag inflators, free of charge. The recall began January 7, 2020. Subaru owners may contact Subaru customer service at 1-844-373-6614. Saab owners may contact the Saab Customer Assistance Center at 1-800-955-9007. Subaru's number for this recall is TKB-20.
AIR BAGS:FRONTAL:PASSENGER SIDE:INFLATOR MODULE · 20V003000
2020-01-02 · EA15001
Subaru of America, Inc. (Subaru) is recalling certain 2009-2013 Forester, 2003-2006 Baja, 2004-2011 Impreza, 2004-2014 WRX (including STI), 2003-2014 Legacy and Outback, and 2005-2006 Saab 9-2X vehicles originally sold, or ever registered, in the states of Alaska, Colorado, Connecticut, Idaho, Iowa, Maine, Massachusetts, Michigan, Minnesota, Montana, New Hampshire, New York, North Dakota, Oregon, Rhode Island, South Dakota, Utah, Vermont, Washington, Wisconsin, and Wyoming or "Zone C."
These vehicles had their passenger frontal air bag inflators previously replaced under a prior recall using inflators of the same design. The inflators may explode due to propellant degradation occurring after long-term exposure to high absolute humidity, temperature and temperature cycling.
Consequence: An inflator explosion may result in sharp metal fragments striking the driver or other occupants resulting in serious injury or death.
Remedy: Subaru will notify their owners. General Motors will notify Saab owners. Dealers will replace the passenger air bag inflators, free of charge. The recall began January 7, 2020. Subaru owners may contact Subaru customer service at 1-844-373-6614. Saab owners may contact the Saab Customer Assistance Center at 1-800-955-9007. Subaru's number for this recall is TKC-20.
AIR BAGS:FRONTAL:PASSENGER SIDE:INFLATOR MODULE · 15V323000
2015-05-28 · EA15001
Subaru of America, Inc. (Subaru) is recalling certain model year 2003-2004 Subaru Baja vehicles manufactured January 22, 2003, to July 21, 2004, 2004-2005 Impreza vehicles manufactured January 28, 2003, to May 31, 2005, 2003-2008 Subaru Legacy vehicles manufactured January 22, 2003, to May 2, 2008, 2003-2008 Subaru Outback vehicles manufactured February 18, 2003, to May 5, 2008, and 2005 Saab 9-2x vehicles manufactured February 11, 2004, to March 17, 2005. The affected vehicles are equipped with a passenger side frontal air bag that may be susceptible to moisture intrusion which, over time, could cause the inflator to rupture upon its deployment.
Consequence: In the event of a crash necessitating deployment of the passenger's frontal air bag, the inflator could rupture with metal fragments striking the vehicle occupants potentially resulting in serious injury or death.
Remedy: Subaru will notify their owners and General Motors will notify Saab owners. Dealers will replace the passenger air bag inflator, free of charge. The Subaru recall began on June 17, 2015. Owners may contact Subaru customer service at 1-800-782-2783. The Saab recall began on July 27, 2015. Owners of Saab vehicles may call 1-800-955-9007. Subaru's number for this recall is WQR-53. Note: The recall completely supersedes recall 14V-399 (WQL-48) and partially supersedes recall 14V-763 (WQP-51) in that model year 2004 through 2005 Subaru Impreza and model year 2005 Saab 9-2x vehicles are now only part of this campaign. Note: On December 18, 2015 Subaru informed NHTSA of an expansion of this recall to include certain model year 2003-2004 Subaru Baja, 2003-2008 Subaru Legacy and 2003-2008 Subaru Outback vehicles.
SUSPENSION:FRONT:CONTROL ARM:LOWER ARM · 11V464000
2011-09-06 · PE11011
SUBARU IS RECALLING CERTAIN MODEL YEAR 2002-2007 IMPREZA, MODEL YEAR 2003-2008 FORESTER, AND MODEL YEAR 2005-2006 SAAB 9-2X VEHICLES MANUFACTURED FROM SEPTEMBER 5, 2000 THROUGH NOVEMBER 26, 2007 ORIGINALLY SOLD, OR CURRENTLY REGISTERED IN, MASSACHUSETTS, MARYLAND, MICHIGAN, NEW HAMPSHIRE, NEW YORK, PENNSYLVANIA, VERMONT, WISCONSIN, CONNECTICUT, DELAWARE, IOWA, ILLINOIS, INDIANA, MAINE, MINNESOTA, MISSOURI, NEW JERSEY, OHIO, RHODE ISLAND, WEST VIRGINIA AND THE DISTRICT OF COLUMBIA.
THE FRONT LOWER CONTROL ARMS MAY BREAK AT THE HANGER BRACKETS DUE TO CORROSION IF THE HANGER BRACKET IS EXPOSED TO SALTY AND HUMID ENVIRONMENTS SUCH AS ROADS CONTAINING SNOW MELTING AGENT.
Consequence: A BROKEN CONTROL ARM CAN RESULT IN THE LOSS OF CONTROL OF THE VEHICLE, INCREASING THE RISK OF A CRASH.
Remedy: SUBARU WILL HANDLE THEIR VEHICLES AND SAAB WILL HANDLE THEIRS. DEALERS WILL INSPECT THE DEGREE OF CORROSION OF THE FRONT LOWER CONTROL ARMS, AND WILL EITHER RUSTPROOF OR REPLACE THEM. THIS SERVICE WILL BE PERFORMED FREE OF CHARGE. THE SAFETY RECALL IS EXPECTED TO BEGIN DURING DECEMBER 2011. OWNERS MAY CONTACT SUBARU AT 1-800-782-2783. OWNERS MAY CONTACT SAAB AT 1-800-955-9007.
ENGINE AND ENGINE COOLING · 04V473000
2004-10-01
ON CERTAIN PASSENGER AND SPORT UTILITY VEHICLES, THE COVER BOLTS FOR THE ENGINE OIL CONTROL VALVE MAY NOT BE SUFFICIENTLY TIGHTENED, ALLOWING OIL TO LEAK FROM AROUND THE COVER GASKET.
Consequence: IF LEAKING OIL CONTACTS COMPONENTS OPERATING AT HIGH TEMPERATURES, A FIRE COULD RESULT IN THE ENGINE COMPARTMENT.
Remedy: DEALERS WILL INSPECT AND RETIGHTEN THE OIL-FLOW CONTROL VALVE COVER BOLTS. THE RECALL BEGAN ON OCTOBER 8, 2004. OWNERS SHOULD CONTACT SUBARU AT 1-800-782-2783.
VEHICLE SPEED CONTROL:CABLES · 04V128000
2004-03-16
ON CERTAIN PASSENGER SEDANS, WAGONS, AND SPORT UTILITY VEHICLES, THE CRUISE CONTROL CABLE COULD COME OUT OF ITS TRACK ON THE CRUISE CONTROL LEVER AND LODGE ON THE CONTROL LEVER TAB WHEN THE ACCELERATOR PEDAL IS RELEASED. IF THIS CONDITION OCCURS, THE THROTTLE WILL NOT RETURN TO THE IDLE POSITION AND WILL REMAIN IN AN OPEN POSITION.
Consequence: IF THIS OCCURS DURING VEHICLE OPERATION, THE DRIVER COULD LOSE CONTROL OF THE VEHICLE, WHICH COULD RESULT IN A CRASH.
Remedy: DEALERS WILL INSTALL A CRUISE CONTROL CABLE RETAINING CLIP TO THE CRUISE CONTROL LEVER TAB ON THE THROTTLE SHAFT IN ORDER TO PREVENT THE CRUISE CONTROL CABLE FROM COMING OUT OF ITS TRACK. OWNER NOTIFICATION BEGAN ON APRIL 12, 2004. OWNERS SHOULD CONTACT SUBARU AT 1-800-782-2783.
Building an app?
Free API access to all this data — 50 requests/day, no card required.