I recently bought a subaru gf2 1.5 1999 Model and immediately i took it for service where plugs, air filter and all oils were chaged. Unfortunately it is still consuming 1 litre for 5 km. is it normal or it can do better? and if not possible what is the probable cause? i will appreciate your helpful responses.

After having the car tuned up with plugs etc. how well is the motor performing? Do you have plenty of power, with no hesitation?? How many Km on the odometer?? Any blue smoke coming from the exhaust? If motor is running great, there may not be much that can be done to improve fuel millage.

Not normal. Converted to mpg you are getting around 12 miles per gallon which is really bad. My guess is this model should get at least 30 miles gallon. 

probable causes? quite a few.

 

NGK plugs installed? any oil on the plug wire boots?

 

any CEL codes set? have then read and post them up.

 

knock sensor, engine temp sensor, O2 sensors, MAF/MAP etc.....

Edited August 24, 201510 yr by 1 Lucky Texan