Madasafish

Many people fill their tanks up so they can get no more fuel in. This means that the pipework leading from filler to tank is full of fuel - I reckon 4-5 ltres worth. Tank based measurments don't show this.. So the first quarter of the tank really shows a long time to empty because it is a lot more than a quarter of the tank's worth of fuel.. Never had that problem with my 1929 Riley Nine. The fuel tank was a cylinder mounted on the front bulkhead behind the engine above the driver's feet.. To fill it, open the bonnet..No pipework at all...

Basic tests are: check plug gaps, check air filter,check oil is clean (if not the VVTI mechanism - driven by oil pressire - may not work properly) You don't mention those: which cost nothing to do.

Agreed..I pesonally would not want to spend any more than I have to on a 17 year old car...that's 3.5 years older than the UK average life of a car.. ohh our Yaris is 16 years old...

Xheck the fuel pump works.. Should whirr slightly when switched on -

The way to identify a current drain is to remove fuses one by one until you remove one that makes the drain stop. (Edit: and repalce each in turn if removing makes no difference or you may have a heap of fuses and don't know where to put them!). Usual suspects are interior lights both in cabin and in boot..Might take a while.. but it is not rocket science..

10mm - per digital caliper - on our 2003 D4D - built in Japan. French built cars may be different..

You need an all singing and dancing reader..not a generic one.. Not cheap..

The coolant temperature sensor controlling the ECU running of the gearbox is entirely different from the sensor which controls the temperature coolant light..

Well done. A tribute to perseverance..

"The sat nav wouldn't work- the touch screen just didn't respond at all. The guy said he would fix or replace " So why did he not do so before selling? Answer : he's a cheapskate and probably a liar as he'll bodge it . An honest seller would fix it first. Run away: lots more around

Check the plugs first..

Yes BUT You need to remove the crankshaft bolt. See above... Having done it once when I replaced the chain on son's Yaris I would never do the job again. ..... ever

Re: non starting: you don't mention checking sensors.. Crankshaft sensors fail. They work OK when cool.. And then break down when hot. Try a s/h one.. Is the timing chain noisy? Have you checked the PCV valve? Flushed the engine? Eliminate everything else before stripping anything..Reassembly will be fun if you still find it does not start... My guess is poor maintenance and lumps of crud moving round oilways..or a combination of issues..

As Frosty above. But the engine changed post 2005. Pre 2003 engines will have the same HG vulnerability.. So best are 2003 to 2005 engines..

I think if you lived anywhere else in the UK - ie.places where they do have winter! , you might notice a difference in wet weather grip...