Good morning all!

My last petrol tank refill last me 230 miles approx, for 37 liters of petrol.

I did some maintenance last WE (oil change, oil and air filters, spark-plugs), thinking that it would correct its drinking problem. Thing it did, but not the way I hoped... Last night was kind of the first "long" trip I did with the car, almost 40 miles ^^, and I saw the petrol gauge going down as far as I drove! :eek: Pretty scary!

Can you tell me what could make the car over "drinking", without the performance output unfortunately... And how to fix it... Please.

For the record, the car is parked at the same place everytime, and there is no sign of any leak. I only notice some liquid getting out from the exhaust. I don't know what is it yet. I did my maths, and it's around 23.4 miles per gallon, or 10 liters for 100 kms, which I found pretty HUGE for a 1.3l MPi!!!

Any help will be more than welcome!

Valve clearances is the only thing you've left off that could significantly influence MPG. Is probably also worth cleaning the throttle body butterfly valve with carb cleaner, and sticking some redex in the fuel tank.

Another thing that may need looking in to is the thermostat and temperature sender. Where does your temperature gauge sit, and how long does it take to get there from cold?

Liquid coming out of the exhaust could just be condensation - but do check under the oil filler cap for "mayonnaise" and check the coolant level.

Would also try examine around the petrol filler and filter under the exhaust heat shield to check for any leaks if none of the above does anything. Petrol may well evaporate, although I imagine you would have the obvious petrol smell on the ground.

I do find that around town the car can drink quite a lot... and even on long runs, unless you're doing 60mph or less, it can also "drink" a bit!

On our trip to germany we averaged 42.8 mpg over 1300 miles and that was with doing around 65 mph all the way!

I do notice big changes in the amount of fuel it uses depending on driving style.

Phil

Thanks anewman, I'll do check what I can this WE and let you all know about it.

Thanks also philje123 for your report. Just to let you know that I'm not a high RPM driver, I just stay into the green part of the meter on the dashboard!

I was driving on a dual carriage way, around 60-70 mph for 30 minutes, not city driving. This is why I worried as it might be more while driving in the city!

My SWMBO has a 1.6 she does a lot of town driving and thrashes the nuts off it, she gets about 250 miles to a tank.

With to-day's petrol prices I can well understand your concerns, and 23.4 mpg sound absurd, really.

With my 1.6 a steady 70 mph gives me at least 40 mpg and the 1.3 shouldn't differ too much, maybe it drinks a bit more at higher speeds but less if you go slower.

I would have thought that anything less than 35 mpg with the 1.3 engine would deserve either that you're stuck in congestion or that you are a really "spirited" driver, constantly taking it just up to the red sector of the rev counter.

Tyre pressure affects mileage, but only marginally - could be wise to check anyway. Thermostat/temp sender, as mr. Newman suggests, could be another explanation. Broken piston rings/insufficient compression? But then surely you would have noticed oil consumption as well.

I don't know a thing about injection and ECUs but a maladjusted carb can affect fuel consumption badly, and I guess that something similar could happen to injection systems as well. In that case I guess that it will show up with a vag-com test?

If the temp guage isnt reading around the mid point when warm , i would put a new temp sender in it as the sender could be telling the ecu that the engine is cold and giving it extra fuel (ie choke )

my felly always seems to get me over 100km's for just over 6 liters or "1.6 gallons"

and oh...it's on the "yellow gas light" the whole time!

First of all, I am a technician, not an expert in car one, but I have a general good knowlegde to open things up (computers, devices, washing machines, etc...), clean them, put them back together, and make the thing still runs!

So, my question would be :

Can I myself clean the injectors with some carb cleaners, or else..?

Or is it better to let the professionals do their job..?

I owned a 84 Vauxhall Kadett for 3 years, and did a lot of work on it, but at this time, I had a carb mounted on! ^^

And also, the first thing I had to replace was the temp sensor, as I had hot restarting problem due to it!

When I drive on country-side road, the temp reading is around 90, on highways just above 70, and can reach 100-110 during city driving (stuck in traffic for a long time!). It looks normal to me, but let me know if something's wrong!

When I drive on country-side road, the temp reading is around 90, on highways just above 70, and can reach 100-110 during city driving (stuck in traffic for a long time!). It looks normal to me, but let me know if something's wrong!

I would say that the reading ought to be the same on countryside roads and highways - around 90 in both cases. My temp gague sits very stable around the 90 mark no matter what kind of roads - even in freely flowing city traffic. The temp decrease on highways could point towards a faulty thermostat (or broken stat housing) that doesn't close. In winter the faulty stat symptoms can't be overlooked, since the temp never rises above 70 unless you get stuck in traffic. If the temp sender works correctly it will tell the ECU that the engine hasn't quite reached working temperature, and this will of course affect fuel consumption a bit. But 23.4 mpg is a unusually high figure...

Pretty easy to change, but it's recommendable to change both stat and housing, since the latter easily breaks (plastic).

The temperature sensor is a combined unit incorporating a fuel injection temprenture sensor.

According to Mr Haynes it works like this..... The Fuel injection/ECU supplies the sensor with a set voltage and then by measuring the current flowing into the sensors circuit it determines the engines temperature. This information is then used in conjunction with other inputs to control the injector timing, the idle speed etc.

If the sensor circuit should fail to provide adequate information the ECU back up facility will override the sensor signal. In this event the ECU assumes a predetermined setting which will allow the fuel injection/engine management system to run, albeit at reduced efficiency.

Based on this info i would place my bets on it being the sensor. Nice and easy to replace and you should also see an improvement in running and performance

Won't dispute Harry's or Mr Haynes' wisdom, but it seens as if DooDle already has replaced the sender?

But still, if the engine is "over-cooled" due to a broken/constantly open stat, a good sender will send inaccurate information to the ECU... still, the difference between 70 and 90 C seems to small to explain the unusually high fuel consumption :confused:

Won't dispute Harry's or Mr Haynes' wisdom, but it seens as if DooDle already has replaced the sender?

Yes, I already change it!

So, I'll have a look to the thermostat, thanks for the advice!

Small update, which seems to be a bad one. It looks like I'm losing petrol from an area just under the spark-plugs!

I checked my oil level, as I did change it last week, to see if there was any leak. Everything's OK from this side.

My coolant level didn't move at all, and no sign of "mayonnaise" under the oil filler cap, the oil is still clean!

What I have in my mind now is : One of the spark-plugs is not tighten correctly, and may leak (I hope so!!!), if not, it would mean I have another leak somewhere else!

One of the spark-plugs is not tighten correctly, and may leak (I hope so!!!)

Yes, let's hope it's that simple and that it's just a matter of tightening the plug so that the thread hasn't gone bad :eek: (can be fixed, but requires specialist tools).

Might be wise to check the stat anyway since it's a very common Felicia problem - or at least do it before winter!

I just checked the spark-plugs, and one was not tighten enough.

The faulty one, i was able to move it with my fingers...

So, by prevention, I checked all of them, and re-tighten the last one. :P

I just came back from a quick tour, and the car was responding 100 times better than 2 hours ago. I think it was part of the problem.

Why part of it..? Because I checked the engine, and took some pics. I attached them and we can see what could be a leak from the metal pipe piece which arrives on top of the cylinders, the piece where the injectors are, but at the bottom of it (I think it's called manifold, not sure of that).

I'll keep an eye on it for the next refill, and check its "drinking" problem...

For the thermostat, I'll plan to do all the cooling job at once (radiator fan switch also, just in case), as I'll have to replace the coolant liquid to check it.

Thanks for your support all! I really appreciate!!! :orb_cool:

250 mies to a tank! glad I dont pay your fuel bills Alex!!

Mine can nudge 400. or in town drivbing at least 350

looking at the pictures , i dont think you have anything to worry about with a bit of oil leaking from the side plate gasket

Agreed; if you're bothered, clean off the oily areas with old rags or paper, then keep an eye on the area.

The oily area is *very* easy to sort out. Front cover (cam cover) gasket is under £2 from dealers and the 4 little seals around the 10mm nuts should cost next to nothing too. But as already said doesn't look like anything of particular concern. Something to add to a parts shopping list though if you're going to order a few things