Q: check engine light on, 1990 Subaru Legacy

asked by on August 24, 2016

Loses power when going long steep hill. Sta.wagon has slightly strong fresh gas emissions. Replaced knock sensor, spark plugs, oxygen sensor, cleaned mass air flow sensor. Replaced fuel injectors.

My car has 140000 miles.
My car has an automatic transmission.

Hi there, thanks for writing in about your 1990 Subaru Legacy. You need to have the fuel pressure tested to see if the fuel pressure is within specifications and will hold pressure after testing with engine off. The fuel pressure regulator may be leaking excess fuel into the [intake manifold causing it to run rich. Scan the computer to access codes and diagnosed them as needed. Make sure there is no leak in the intake hose between the mass air sensor and the throttle body. If you need to have this done, a certified technician from YourMechanic can come to your home or office to inspect the Check Engine Light and let you know what should be done.

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