compression loss, lousy fuel consumption

[Civicvic]

Have a 2013 civic ex auto, 77000km (48k miles), lousy 18mpg (12.5 l/100km) city, no error codes.

Did a compression test: 200-180-180-189 psi. Guessing about 20% compression loss. Does the compression loss explain lousy fuel consumption? How should a new engine test for compression?

 

[webby]

Without access to a service manual or someone at Honda chiming in, this is info I saw for other r18 engine. I would imagine it is almost the same for the 9th gen r18 engine.




I’ve seen people report 170’s-190’s for psi on the k motors.

Are you burning oil between changes? How’s the air filter look? How’s the tire pressure? Have you done any cleaning to like the maf sensor? O2 sensor original? Any intake/exhaust modifications?

 

[sunofwolf]

those numbers look normal, so its not the problem. Have the dealer hook it up to their computer, find the problem fast or perhaps a up to date mechanic with a scanner.

 

[Civicvic]

Thanks for the responses, it's appreciated.
I just bought the car used. It has new spark plugs, new pcv valve, new air filter. Tire pressure is a little high. Two mechanics have seen the car, reporting no error codes. I would expect a faulty oxygen sensor to produce a code. Are these sensors maintenance items?

My research shows a new r18z1 engine should have 215+ psi compression (10.6:1). An engine with 128psi compression might run but perform poorly. Wouldn't any loss of compression proportionately affect performance?

Edit:
MAF sensor is hard to get to in this car. This car is a little stupid to work on. Even checking the coolant level is hard.