The Check Engine Light may illuminate because of low catalytic converter efficiency. This same issue may cause the car to fail the State Smog Test if one is required.
The head gasket has a high failure rate due to cooling system problems. Subaru is aware of the problem and has extended the warranty to 8 years/100k miles on many vehicles.
An oil leak can develop from the spark plug tube seals. Excess oil in the spark plug tubes can result in engine misfires and illumination of the Check Engine Light . Our technicians tell us that removing the valve cover and replacing the tube seals and cover gasket is necessary to correct this concern. Oil damaged spark plugs, ignition wires , and ignition coils will also require replacement.
Front engine oil leaks can develop from the camshaft seal and the crankshaft front seal . If one or more seals require replacement, it may be wise to consider replacing the timing belt as well. These seals are commonly inspected and replaced as needed as part of a timing belt service.
Sometimes the Check Engine Light illuminates because the computer detects misfires. Subaru released an improved spark plug wire set to solve the problem. The ignition coil should also be inspected for carbon tracks or short circuits between the contacts
The Check Engine Light may illuminate because of a failed knock sensor . Although the sensor often tests okay, it can fail intermittently, while the vehicle is being driven.
related to trouble-codes, p-codes-powertrain, p0400-p0499, p0456
related to suspension, strut
related to engine-cooling, add-coolant
related to security