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Discussion Starter · #1 ·
Hiya folks,

Believe to have an issue with my ST running rich, mpg is abysmal even on long runs mpg doesn't go above 20, most of the time it hovers around the 17-18mpg mark. Because of this i believe the car may be running rich, what would be recommended to diagnose this issue ?

Also regarding boost, am i correct in thinking that boost goes to 1/4 for under 4k rpm in any gear and above 4k rpm 3/4 boost ?
 

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QUOTE(madmossy @ 14 Nov 2009, 12:41 PM) <{POST_SNAPBACK}>Hiya folks,

Believe to have an issue with my ST running rich, mpg is abysmal even on long runs mpg doesn't go above 20, most of the time it hovers around the 17-18mpg mark. Because of this i believe the car may be running rich, what would be recommended to diagnose this issue ?

Also regarding boost, am i correct in thinking that boost goes to 1/4 for under 4k rpm in any gear and above 4k rpm 3/4 boost ?

The boost sounds about right for a standard car but the MPG figures dont! Are the tailpipes very black and sooty? Has the car been serviced recently? Might be worth just checking the air filter for obvious signs of dirt, leaves etc? Hope that helps!
 

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Discussion Starter · #3 ·
QUOTE(fishface31a @ 14 Nov 2009, 01:03 PM) <{POST_SNAPBACK}>
The boost sounds about right for a standard car but the MPG figures dont! Are the tailpipes very black and sooty? Has the car been serviced recently? Might be worth just checking the air filter for obvious signs of dirt, leaves etc? Hope that helps!


Car was given its 3 year service just before a i bought it, not sure what to look for on the tailpipes, the outside parts are fine but i do clean the car on a regular basis, will take a look at the air filter now, was gonna take it to local ford garage and get them to take a look as its still covered by the ford direct warranty.
 

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I've read several posts on various forums regarding the MAFs - when these deteriorate the mpg will suffer

how many miles has your car done?
 

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Discussion Starter · #5 ·
Cars done just shy of 35k, went to garage but they closed at 12:30 so will have to wait till monday now.

Figured it could possibly be the MAF after reading up on similar issues, any tips or tricks I can try ?
 

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the ST has been designed to run a bit rich by ford.Less mpg but more importantly for them less warranty claims.But yours seems very low.I would get it checked over tbh
 

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QUOTE(madmossy @ 14 Nov 2009, 02:57 PM) <{POST_SNAPBACK}>Cars done just shy of 35k, went to garage but they closed at 12:30 so will have to wait till monday now.

Figured it could possibly be the MAF after reading up on similar issues, any tips or tricks I can try ?

The only way to test it is to either use a Ford diagnostic system or swap it over for one you know works! Have you got any warning lights on on the dash? When mine went it threw up the ESP warning light and the engine warning light! If you know someone with a Dreamscience handset they could read if there are any error codes for you? If the car is standard and the MAF goes it usually reduces the boost to 1/4 maximum! Mine was running the DS map and the only difference in running was that the ESP didnt work! Other than that the car ran perfectly!
 

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QUOTE(fishface31a @ 15 Nov 2009, 11:31 AM) <{POST_SNAPBACK}>
The only way to test it is to either use a Ford diagnostic system or swap it over for one you know works! Have you got any warning lights on on the dash? When mine went it threw up the ESP warning light and the engine warning light! If you know someone with a Dreamscience handset they could read if there are any error codes for you? If the car is standard and the MAF goes it usually reduces the boost to 1/4 maximum! Mine was running the DS map and the only difference in running was that the ESP didnt work! Other than that the car ran perfectly!


Can't be the MAF then as I discovered the other night when some idiot chav in his chavved up saxo tried to out pace me, as the boost gauge went almost into the red when I hit 4k rpm in 4th. Honestly don't know why they bother unless they like being made to look a fool in front of their friends.
 

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Graham - mk2 stage 3
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QUOTE(madmossy @ 15 Nov 2009, 12:16 AM) <{POST_SNAPBACK}>reset every fill up


Are you just re-setting the miles run? This will not re-set the average mpg - you will have to do this separately. If you don't, the average mpg will be calculated from the last time the average mpg was re-set and it takes a very long time for any changes to come through, maybe at a rate of 0.1 mpg per day.

Select the average mpg and re-set it. Initially there will be quite large differences, but as you put on some mies it will settle. If you mpg read-out does not improve either the fault mentioned might be worth investigating, or maybe tyou need to alter your driving style!

You can double check the average mpg by re-setting the distance run, fill the car right up and on the nest re-fill (to max again) you will know how much fuel you have put in and how many miles you have run. You can then work out your true average mpg.
 

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Discussion Starter · #12 ·
QUOTE(Dabhand16 @ 15 Nov 2009, 02:35 PM) <{POST_SNAPBACK}>Are you just re-setting the miles run? This will not re-set the average mpg - you will have to do this separately. If you don't, the average mpg will be calculated from the last time the average mpg was re-set and it takes a very long time for any changes to come through, maybe at a rate of 0.1 mpg per day.

Select the average mpg and re-set it. Initially there will be quite large differences, but as you put on some mies it will settle. If you mpg read-out does not improve either the fault mentioned might be worth investigating, or maybe tyou need to alter your driving style!

You can double check the average mpg by re-setting the distance run, fill the car right up and on the nest re-fill (to max again) you will know how much fuel you have put in and how many miles you have run. You can then work out your true average mpg.

I reset all dials every fill up, miles done, average mpg and average speed. will doing a long journey next weekend which will be ~300 miles there and back so will see what its like for fuel then, but still gonna go see garage tomorrow, cos for some reason the steering wheel has started to vibrate like crazy when braking from high speed.
 

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Graham - mk2 stage 3
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QUOTE(madmossy @ 15 Nov 2009, 03:02 PM) <{POST_SNAPBACK}>I reset all dials every fill up, miles done, average mpg and average speed.

Spot on. In this case it might be that you are not doing long enough journeys for the consumption to settle. 20mpg in stop-start town driving is probably about right. I tend to do long-ish journeys of around 30 miles most of the time (commuting) and I get 30 - 32 mpg pretty much all of the time. However, a couple of short shopping trips will bring it down to 26mpg ave just like that if I re-set the ave mpg.

I suggest you don't re-set the ave mpg and see how it pans out over two or three fill ups. when my Son had my car he averaged about 25 mpg and my other Son also has an ST3 and he is on 22 mpg ave at the moment. I daresay they drive a bit quicker than me.
 

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Hi Madmossy
I had the same proplem with my st does the car seem a bit sluggish too. if so it will probably be the front lambda sensor. Try disconnecting the sensor`s electrical plug which is located to the right top side of the engine just under the induction pipe near to where the flexi bit is located. the plug has a grey/white collered bit that you just pull up and then the plug will just pull apart . then try driving the car it is ok to do this and you should notice a big differance. You may also get the ecu light up and a fault code but it is all ok as Gary (Wolfman) and John at Profile Automotive did this to mine last weekend and found this to be the problem with mine.
Hope this helps
Kind regards
Nick13
 

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QUOTE(nick13 @ 15 Nov 2009, 04:51 PM) <{POST_SNAPBACK}>Hi Madmossy
I had the same proplem with my st does the car seem a bit sluggish too. if so it will probably be the front lambda sensor. Try disconnecting the sensor`s electrical plug which is located to the right top side of the engine just under the induction pipe near to where the flexi bit is located. the plug has a grey/white collered bit that you just pull up and then the plug will just pull apart . then try driving the car it is ok to do this and you should notice a big differance. You may also get the ecu light up and a fault code but it is all ok as Gary (Wolfman) and John at Profile Automotive did this to mine last weekend and found this to be the problem with mine.
Hope this helps
Kind regards
Nick13

Thanks for the advice nick13, unfortunately I have nothing to compare cars with so what might feel sluggish to you, feels fine for me, coming from a focus 1.6 diesel, even an ST in limp home mode feels faster. I will actually be in the swindon area next weekend, devizes to be exact, will be their for my nieces 1st birthday
 
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