my civic has started guzzlin the petrol lately & i don't know why. i don't boot it or anythin & £10 used to do me for 100 miles or so but this past week i have put £30 in & its nearly empty again. i have covered no extra miles in fact i think i have done less lately.
its due for a service as soon as i get £100 but does anyone have any ideas please?

have u took the cat off recently? changed nethink like that?

no nothin everythin is the same

I've just taken the cat off mine, My civic is also going through a lot of fuel. i use to get about 150 miles to £15, but now I only get about 110 miles. I know some of the difference to the fuel prices and the fact I've got no cat, I an looking into the reason for this..

Hows the car running? Does it feel sluggish?

Few things id check are:

Plugs, Leads (unless it has coil pacs), AFM (maybe give it a clean) and the engine temp sensor (could be running the map for a cold start all the time).

Does the Cars ECU have built in diagnostics? Might be worth spending a few quid at Honda to get it diagnosed if its costing this much extra in fuel.

it has been feeling a bit sluggish & i changed the induction pipe yesterday as per maverick which has solved that problem so maybe its linked-hope so anyway. thanks stuy i'll take a look & thanks mav if you can keep me informed that would be great.

I remember i had a similar problem with my polo, and i was recomended to run some petrol treatment throught the engine, seemed to fix the problem, used the shell optimax for a bit as well.

Coule be the spark plugs, oil etc though.

Get your service paid for and if it is still there then i am sure budding mechanics on the site can help you a bit more