thirsty 306!

[froggy]

My wife"s, 306 petrol, (2000) is suddenly using more fuel. there is no obvious leak, could it be a faulty Oxygen sensor or another type of sesor at fault? any advice greatfully received, cheers Terry .

[spider]

Assume no engine management light on ?

Although you said no obvious leak, pop under the rear wheel arch area to examine the fuel filter. If its metal, they can rot in some cases but this is quite rare and it would have to be old. You might not have one here though.

The other favourite point is where the fuel pipes cross the cylinder head cover although that's more an XU petrol (1.8 / 2.0) concern, I don't think your pipes are in the same place.

If it had a bad o2 sensor I'd expect the light to be on or some rough running (probably more apparent when it was up to temp rather than cold running concerns)

Check brakes are not binding, although it sounds obvious I know and I'd expect it to be more noticeable before fuel consumption was noted.

The only other quick idea I have, although its not quite the weather does the heater / temp gauge work fine ? , I'm thinking a partially stuck open thermostat will cause an increase in fuel consumption as the mixture will be kept richer than it should be until the engine is actually warm.

[froggy]

Cheers Andy.

[Oldpug]

2nd all above. Also I`ve had a few 306`s split the rubber elbow hose that joins the fuel tank to the filler neck.