drinking too much fuel

**glen poole** · 20-05-2009,09:09 PM

Hiya all, i'm getting a little worried as my 1.8t passat is drinking to much petrol, it's strange as on a 6 min drive i averaged 27 mpg but on an earlier run it's saying i used 40 miles worth of fuel but i only drive for 15 miles without booting it, drove very light & carefully, also my temp gauge is not sitting at 90 anymore, around 70 when i'm driving, back up to 90 sometimes if i'm sitting in traffic, i think my thermostat is stuck open? is the temp gauge & the canning of fuel related in anyway? also have a fault code 17087 & 18258, haven't a clue what they mean, any help will be gratefully appreciated, many thanks.

**martin1810** · 20-05-2009,09:35 PM

Don't recognise the codes but I would change the temperature sender.

**glen poole** · 20-05-2009,09:45 PM

i'll give the temp sender a go but i'm not sure where it is? it's a 1.8t on a 52 plate, awt if this helps.

**martin1810** · 20-05-2009,10:11 PM

Back of engine near bulkhead. sensor held in by a clip. You need to by a sensor , new seal and clip.

**PeteK** · 21-05-2009,01:11 PM

Originally Posted by glen poole

Hiya all, i'm getting a little worried as my 1.8t passat is drinking to much petrol, it's strange as on a 6 min drive i averaged 27 mpg but on an earlier run it's saying i used 40 miles worth of fuel but i only drive for 15 miles without booting it, drove very light & carefully, also my temp gauge is not sitting at 90 anymore, around 70 when i'm driving, back up to 90 sometimes if i'm sitting in traffic, i think my thermostat is stuck open? is the temp gauge & the canning of fuel related in anyway? also have a fault code 17087 & 18258, haven't a clue what they mean, any help will be gratefully appreciated, many thanks.

When you say it has used 40 miles worth of fuel over 15 miles, are you getting this info off the distance until empty reading on the fuel computer? If so, these can be very misleading. For example, I did a short journey the other day of approx 2 miles; the DTE stated I had 650 miles left before setting off yet when I returned it only said 600. The DTE should be used as a rough guide only.

**Sam** · 21-05-2009,01:43 PM

When was it last serviced?

How old are the plugs?

**glen poole** · 21-05-2009,08:47 PM

i did an oil change & air filter around two months ago, yet to do the plugs, today when i drove the car the temp reached 90 & stayed there, just town driving, so not sure what is going on?