Honda Civic 1.5 Automatic VTEC hatchback, year 200 - Poor fuel economy - hondacivic2k

Hi there,

I have a Honda Civic 1.5 Automatic VTEC hatchback, year 2000 (Japan Domestic Market import), 163,000kms. The engine is a D153B. LA-EU1. Type G.

The fuel consumption has progressively got worse and I am getting between 23 and 25 mpg. Most driving is around town but the car does get some further runs of around 1 hour.

The car has been serviced by either a local garage or Honda since I owned the car as per the recommended schedule and major work carried out by Honda e.g. cambelt/water pump and a faulty Top Dead Centre sensor.

Honda recently looked at this fuel consumption problem. They replaced the spark plugs, checked ignition timing, valve timing and clearances and fuel mixture which were all within manufactures specs. They checked the air filter and air intake system and then carried out a ECU clear and re-learn.

They ran injector cleaner through a full tank of fuel.

They checked the emissions and found nothing untoward and there were no engine errors or warnings when they plugged in their computer.

The car starts and runs fine, goes up hill without issue and there is no smoke from the car.
I have checked for leaks but cant find anything.

There has been no improvement in fuel consumption with this work done.

I asked about the Lambda sensor, one of which is located at the bottom of the manifold. They said it didnt report any errors.

I am hoping you may have come across this problem in the past and might be able to help or recommend some avenues to check.

Thank you for your help.

Honda Civic 1.5 Automatic VTEC hatchback, year 200 - Poor fuel economy - Bolt

When was auto transmission fluid last changed if it's not been changed as it should that will cause it.

Honda Civic 1.5 Automatic VTEC hatchback, year 200 - Poor fuel economy - Railroad.
If the engine was running rich the spark plugs would be black and sooty, so I seriously doubt that this is the case. There are no fuel leaks, and the emissions check was normal so that leaves you with only one reason for your alleged excessive fuel consumption problem. The way you drive and the journeys you do. Is it possible for you to avoid the short journeys as these will have a serious effect on your fuel consumption?

Check the simple things. Check that the tyre pressures are correct. Switch off all unnecessary electrical loads. Make sure all windows are closed when driving. Remove accessories such as a roof rack if fitted. Avoid full throttle operation, and make full use of overruns, meaning throttle off when going downhill, and anticipate the approaches to roundabouts and junctions by throttling off well in advance. No fuel is injected when throttle position is at 0% and engine speed is higher than 1200rpm. Check also that the throttle valve setting and the potentiometer is correct set. If it isn't then you will not benefit from fuel deceleration cut off.
Honda Civic 1.5 Automatic VTEC hatchback, year 200 - Poor fuel economy - KenC

I agree check the simple things that you can do yourself

tyre pressures (when cold) , are any of the wheel brakes binding ?is the handbrake dragging ? Is the rear silencer box in good condition internally ?

by that I mean if its rusted and collapsed the exhaust gas flow could be obstructed and stifle the engine.

lastly an earlier post referred to the transmission being the cause, I would explore that and ask him for more details.