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Discussion Starter #1
Hi gang, I recently aquired a Espace 2.0 RT-X Auto (its the 8valve one), I am very depressed with the mpg being returned. I drive with a very light right foot and I am only getting 18.87 miles to the gallon.... This cannot be right ? can it ????? I would also say the performance is not what I expected it would be from a relitivly modern engine, I know its old technology now but I get more mpg than that from my 4.2 Landcruiser just ! Any help OR advise please, my thoughts where oxygen sensor maybe ?? anyone know if its a 1,2,or 3 wire one its a F3R engine
 

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Hi Andy, I dont know where the sensor is specifically, but without knowing if that mpg is from town driving or a mixture of A & B class roads, then its hard to tell if its unreasonable.

You can perform a few checks to ensure that the car is as good as it can be without spending cash checking things out unnecessarily;
  1. don't carry excess weight in the car
  2. don't use a roof rack except when you need to
  3. get the tyre pressures to the correct level
  4. check the air filter for blockages
  5. when was the car last serviced? This can cause mpg to rise
These will ensure that the car is at its optimal level of efficiency as it stands.
You may wish to try a tank of higher-octane fuel and giving it a bit of a blast on the motorway - the additives are good at clearing out any deposits which inevitably build-up as part of the combustion cycle.

Try some (or all) of the above, and see how you get on - if the car seems to be running fine, and its only the mpg which is a concern, then in all probability, its just a small bit of adjustment that's needed as opposed to major replacement.

Hope it helps,

Paul:)
 

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andy lambda [oxygen senser] consist of four wires 2 white 1 black 1 grey [f3r engine] espace, before renewing the lambda try a good injection cleaner or two,also check electrical connections to injectors it turned out to be what was wrong with my espace 8 valve f3r also make sure you have the correct sparking plugs fitted you should get at least 30 mpg on a run ------------------------regards
 

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Discussion Starter #4
Thanks folks... all seems to make sense, I have resisted the urge to put through any redex type cleaners to date on the basis that I thought it would be the O/S at fault. The main type of travel is a mixture of town / country A B roads the vehicle is empty apart from me and the Mrs, tyre pressures all correct, I may drop it around to my local gargare and get them to check the emissions and see if they are good OR bad and go from there. The car seems to run fine if not a little underpowered but I put that down to being a 2.0ltr it goes well if you stand on the pedel but thats not the way I drive, I'm very light footed. I had the exhaust inc cat replaced recently and they said the O/S was disconnected when they got underneith it but I seem to doubt that very much as it would flag up straight away I would have thought with service light or something simular. By the way the O/S is mounted in the front pipe just after the manifold connection. the O/S's are not that dear so may just opt to replace it anyway, can't do any harm but as I said I'll get the emissions checked and see what that throws up and go from there. thanks again.
 

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Discussion Starter #6
I'm working it out with calculater and pen as I have to convert from KM to Miles as I also do with with Litres and gallons : 4.54lt = 1 gallon and 1km = 0.62 (approx figs). ie, I put in 12 ltres approx £10 worth fuel and it did 78km = 48.5miles so thats 2.64 gallons returned 48.5 miles = 18.37 miles to the gallon. hoped you followed that, this is how I have calculated the mpg, am I right ?
 

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Oh blimey.....my head hurts after all that!.

Hopefully someone will confirm wether your working it out right,I'm afraid I'm a metric only person and can't convert anything properly.:eek::eek::eek:
 

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Discussion Starter #8
I guess I should point out that I am using the fuel warning light as a starting and end point for my measurements, as in I put in a selected amount of fuel and measure from that point until the warning light shows again. I must admit this is not the best way but its a good indication and cannot be that far out as its a predetermined level that its set at to light up.
 

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If you are doing short journeys, then 19mpg might be about right. Parker's quote the 2.0 to do between 19 (typical urban consumption) - 34 (better than average cruising consumpition at 50 - 60mph) mpg. Add to this the fact that it is auto and therefore heavier will also have an effect regardless of how gentle you are on the throttle.

With short journeys, the car will probably spend most of the time in 'rich' mode as it doesn't warm up adequately to optimum operating temperature so it will probably remain in cold start mode most of the time.

No harm in getting it checked out though - there were some good suggestions there about the last service, tyre pressures etc.
 

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Discussion Starter #10
I've just ordered a new O/S anyway only £16.50 so we'll see if it makes a difference when fitted. Seemed a cheap option. I may as well drive my tank around then if its only going to return 18,5 to the gallon, I get around 20 out of that and its a hugh straight six 4.2 TD. (tank being my Landcrusier, just thoughts I'd say that in case someone thought ...... ) cheers folks, an update to follow in a week or so when I get around to crawling under the car for 15 mins or so.
 

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andy try filling your car to the brim then going for a drive on a set route about 20 -30 miles then refill to the brim at the exact same pump .note how much it takes to refill to the brim again hey presto you know how much fuel youve used and your distance do it three times and you can then work out the average (this takes into acount trafic lights etc ) i did this with my espace tdi now know im getting about 34 mpg from mine .
 

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UPDATE. a strange thing happened this morning:confused: I pulled into my local petrol station stopped at the pump realised I was too far away from the pump reversed back and drove forward only to find I had a rock hard brake pedal ?? Umm well I was dressed in me 9's so didn't want to get dirty so time to call the AA, they arrived within 20 mins and found that the vacuum pipe had come away from the fuel injection module. he re trimmed the rubber pipe and refitted it and hey presto brakes back 100%...... Now I was thinking that if this pipe has been loose or split then it would have been sucking air in for some time. this would affect the mixture reaching the engine, or moreover the electronics would try to richen the mixture by pumping in loads of fuel in to compensate for too much air. So maybe inadvertently this has found the problem not only with the brakes but maybe the fuel economy problem. I'll monitor it for a week or so and see what happens and update you all soon.
 

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It is possible,I suppose.:)If the Lamdba sensor is telling the ECU that the mixture is constantly lean,then the ECU will richen it up,but if it reaches a maximum level and stays there,then it will throw the management light on....in most cases,anyway.:rolleyes:

Keep us updated.:)
 

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Discussion Starter #14
point taken re engine management light but if it was slightly intermittant or just a small leak to start then I guess it may have fooled the ecu into thinking it was just a lean rich state ? We'll see in time I guess
 
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