Subaru 3.0 Engine Problems

Starting in the late 1990s, Japanese automaker Subaru installed a 3-liter hemispherical (Hemi) six-cylinder engine called the EZ30 on some of its vehicles -- namely the Tribeca, Legacy and Outback, which is the wagon offshoot of the Legacy. The Outback has experienced problems.

Major Problems

Some Subaru Outbacks of the 2001 to 2003 model years may experience failures of the catalytic converter, air-fuel ratio sensor, knock sensor and/or the cylinder head gaskets. These problems can trigger the "Check Engine" light, and drivers may experience engine stalling, coolant leaks or overheating.

Minor Problems

Although the 2004 Subaru Outback is virtually free of the aforementioned issues, it has an occasional problem with the failure of the oxygen sensor. This causes the "Service Engine Soon" indicator to illuminate, and the vehicle could fail emissions.

Cost of Repair

As of December 2010, MSN.com estimates repair costs as follows: $1,055 to replace the catalytic converter, $200 for the air fuel ratio sensor, $162 for the knock sensor and $595 for the cylinder head gaskets. In some extreme cases related to the aforementioned problems, the mechanic working on the vehicle may need to reprogram the engine control module as well; this can cost an extra $98 for labor. The oxygen sensor is estimated at around $238.

References

• MSN Autos: 2001 Subaru Outback; Reliability
• MSN Autos: 2004 Subaru Outback; Reliability