Poorer fuel consumption

[P7TNY]

good morning folks,

My car is now nearly nine years old, and has 118k on the clock. It has a very good service history and only does 6-7 a year maximum. I use it mainly for short journeys and my fuel consumption seems very poor at present, I rarely drive over 3 k on the revs counter, and check and top up oil regularly. I have not changed the sparkplugs for a few years. I have had a faulty heater valve for a while now and the fans are blowing hot, would this lead to a inferior fuel consumption. Any hints or tips on how I can improve my consumption. Would disconnecting battery help ??
Thanks in advance

 

[XIIVVX]

First thing I would try is to take the car out, warm it up properly and then really give it a thrashing.

Never running above 3K is no good for an engine designed to be high revving. It is probably all sooted up inside.

A good long run at high revs, maybe even leaving it in third to stay at the legal limit if this concerns you.

This is known as an 'Italian tune-up' and can be quite effective.

After that, changing the spark plugs would be a priority for me.

 

[Dal]

Echo's above k:
Give it a damn good thrashing (once nice and warmed up) to clear out the cobwebs that will do doubt have built up.

 

[P7TNY]

Cheers guys, I was highly concerned about the spark plugs. I shall take the car out soon and drive it at high revs and get rid of the cobwebs. I plan to chnage plugs after car has its MOT later in the month.