got a focus st170 drives nice I like it but it is DRINKING petrol! I put £40 in it driving normaly and I got 130 miles out of it! 1st thing I checked was for a leak! but nothing had a scanner to hand so scanned it and nothing. so took it down the road and got an emissions test done. the lambda is up at 1.7 and hc is wayyy up at 0.700!! so clearly this is the problem. I serviced the car only a month ago. new cambelt and waterpump too. ut drives and runs lovely feels fine. what else could cause this ? any ideas also had a new stat aswell just seeing if there anything common on these. I know there juicy anyway etc etc but iv worked it out and im getting 19mpg!!! any ideas ?

 

A lambda of 1.7 means there's a lot of oxygen in the exhaust gasses.
Probably a substantial leak in the exhaust manifold, this will fool the oxygen sensor(s).

 

19mpg, that's not bad. I get about 24mpg on a run, and at great speed it will drop to around 14-16mpg
My car is serviced well in advance of anything needed doing, and I work at a Ford dealership, so it seems to pretty normal.

 

that aint normal mate. im driving the car like a girl!!! and I mean that becayse iv got black box insurance. im a technican by trade for volkswagen. I just wanted to know if there was anything common on these cars before I start digging. my friend had an st a year or so ago and he was getting about 30mpg out of it.... my brother has a bm 645 v8 and that does 16 per gallon...

 

I think Ford quote 22mpg for urban use, although I can check when I get into work tomorrow..

But they aren't brilliant. Mine has new plugs, oil, filters every 3000miles, but as I said, it's mainly used in 2nd and 3rd gear

 

That's about right for one of these.

And I think your maths is a bit of ,

Your getting 24.5 mpg. Which is all your going to get. I only get 100 miles to 40 quid out of my focus rs.

 

30.76 liters of fuel to 130 miles = 19.21mpg my maths are correct

 

plus I know its running rich from the hc.

 

Do you mean HC 700ppm (seven hundred)?

Or do you mean 0.700? As in less than 1 (0.7)

1.7 lambda would indicate a lean mixture.

0.7 lambda would indicate rich (on an idle/fast idle emission test)

 

Sounds right that's why I sold mine and my dad sold his fuel consumption on st170's is a joke

 

They are hugely shite on fuel, not a problem with your car I'm afraid!

 

And sorry bud but all of us above are currently or have been owners of st170 and we're all telling you the same thing and mine and my dads were from fords so not 2nd hand

 

I agree that I know it isnt going to be good on fuel. but its still not right and thsts my point.

 

Haveyou had the fault codes read? the inlet runner motors / linkage fails on these, doesnt always put the MIL light on, my mates one did it, started, ran fine but was shite on fuel, google / youtube it, we followed the guide on youtube but it didnt fix it, put a new motor / linkage on it, sorted!

 

hi mate ment to mention I already done this fix as wen I 1st got the car it had the mil light on for runner stuck open! thats working fine iv checked it fuel is the same as wen that wasnt working to how it is now. also lambda was 1.70 so high... which I know indicates lean. hc was 0.700ppm which indicates rich

 

There binge drinking is well known for what frankly is not a particularly fast car, but yes as said if it's running lean the it will be running rich, thus using more fuel!

Martin

 

simple things like making sure it gets up to temperature could cause huge fuel consumption

thermostat broke on my mondeo and the mpg dropped to single figures (not that i was great in the first place around town as i was used to getting 17-19 mpg but with the thermostat it was COLD inside too)

 

i done a stat on it when i 1st bought it. i put another £40 in and drove from london to norfolk and back and when the light come on i hit 240miles!!! so 110 miles more than last time... ok alot of it was motorway but alot was also traffic etc. so that works to 35.4 mpg. thats a bit of a difference. maybe the fuel i got was pisswater!!

 

Have you reset the ECU?

Take the battery off overnight. Put it back on then drive it like a granny for the first few miles. Might improve it as I am lead to believe they have a learn function.