Focus Mk2 Burning Oil And Very Poor Fuel Economy

[YnyrCymru]

Right my first post on this forum so please forget the bad spelling mistakes I do hah!

My car is a 2003 Ford Focus 1.6 Zetec SE done about 75,000miles.

Im a 17 year old apprentice mechanic, and this is my first car. I bought the car back in March this year and when I first tried it I was misfiring like a Bi*ch but a new coil pack and spark plugs sorted this problem. Anyway I noticed after few months driving my car I noticed its fuel economy was awful averaging about 26.5 mpg!! So I gave it a service about month and half ago. The fuel and oil filer was changed (didn't change the air filter because I just fitted a Cone air filter on it). I knew with the Zetec's that it had to have a special kind of oil so I put the specific oil in it. Now the problem-I looked the oil level on a dipstick 2 weeks ago and I noticed I was below low so I added about 1/4 litre of oil into it. So I checked again last Saturday (30/11/2013) on the dipstick and it was on low AGAIN! And I've only done about 100 miles. Also I changed my spark plugs again that day and they were black and oily. I've asked my lecturer in collage what he that was the problem, so he started my car and listened as I said I wasn't running 100%,with one cylinder sounding dodgy was his opinion. And also he noticed there was a lot off soot on my twin bore exhaust. So his thoughts was that the car was running rich(which would answer the poor fuel economy and burning oil). And the car is going good aswell! So what could be the problem?

Thanks in advance gentleman!

[btmaldon]

If you only put a quarter of a litre of oil in it when it was below the low line then it would still be giving you a low reading, as that wouldn't have been enough to take it to the maximum. Min to max is nearer half a litre.

Were the plugs gapped correctly. The manual may say 1.3mm but Ford have changed this to 1mm as it was causing poor running.

The cone filter is likely to reduce your mpg as they suffer from heat soak due to poor air flow under the Focus bonnet. You would have been better off fitting a new standard filter for better performance and economy. It just doesn't make the intake noise which gives the impression of more speed.

If it has been running rich or you have just run the engine for a short period from cold before checking the plugs, they could look oily but it may just have been unspent fuel. I would check your oil breathers are all clear, check the intake system and vacuum pipes are clear.

It could be running rich because the temperature sensor to the ECU thinks the engine is cold all the time. Not sure where that sensor is, but it should be separate to the one that goes to the gauge on the dash. I think there is one in the thermostat housing.

Good luck with it.

PS: Your Focus is a Mk1.5 or Mk1 Facelift not a Mk2. That came out in 2005.

[YnyrCymru]

Hi thanks for you're reply, it's greatly appreciated. It was roughly about 1/4 to half a litre of oil,it was on low and after I put oil on it it was on MAX. I did think to check but I didn't as the gap is supposedly correct from the supplier? Yes I knew it would drop its MPG but would it make that much of a different and also there isn't that much difference because I've tried the normal panel filter as well. The car was run for a bit so I was hot and running at optimum temperature I think? I've had a quick check on the breathers and they look normally. I did think it could be a sensor but which one?

Thank you very much for your help!

[stef123]

Hi thanks for you're reply, it's greatly appreciated. It was roughly about 1/4 to half a litre of oil,it was on low and after I put oil on it it was on MAX. I did think to check but I didn't as the gap is supposedly correct from the supplier? Yes I knew it would drop its MPG but would it make that much of a different and also there isn't that much difference because I've tried the normal panel filter as well. The car was run for a bit so I was hot and running at optimum temperature I think? I've had a quick check on the breathers and they look normally. I did think it could be a sensor but which one?

Thank you very much for your help!

I used to have an oil hungry 2001 1.6 focus with the Zetec se engine.

It always returned close to 40mpg on average.

Coil packs are a fairly common fault and I would stick to genuine leads, plugs and coil.

I was going through them at a rate of every 6 weeks - I traced this to a bad earth, once rectified it never happened again.

As for the oil consumption, I never find the cause although I did do a bit of investigation.

It would seem it's quite common on the 1.6 and some reports say it's due to the piston rings - I could find no other cause with mine and put it down to this.

I was starting to use about 1litre every week and always had visible smoke from the exhaust. I passed all my mots but usually only just on emissions. Eventually the car wasn't worthwhile keeping so I traded it in.

It's still on the road and that's been nearly 3 years!

[artscot79]

Sooty pipes dont mean its running rich its common on many cars now even the new mini does it from new sounds obvious but when doing the oil on the focus depending on model its not meant to be at max when cold the manual on some focis like mine state when cold it should be halfway between min and max the plugs are pregapped at the wrong size even now 1.0mm is the correct gap thats what ford state so that wont help the cone filter when the engine heats up will increase economy quite a bit thats a fact as it sucks in hot air from the engine not cool air as is necessary resulting in lower horse power i know ive done it myself dash diagnostics will show the head temp and coolant temp if the sensor was faulty it will show as say -10 on a cold engine its usually 40

[mick85]

First think u need do is a dry an wet compression test very simple check will give u good indication what ur engine is like also if ur car was misfiring for long ur cat an lambda sensor could be damaged also test coolant temp sensor

[wase16ll]

personally, if possible, get an exhaust gas test as this will give everything you need to know about what the engine is doing.

CO/HC/02/CO2 and Lamda...or as many of them as you can

test it from cold at idle and 3k revs...let the car idle for few mins before taking read, plus few mins at 3k

again at mid temp at idle and 3k

again at full temp at idle and 3k

make a note of all the results along with how quickly the reading rises/falls

this will give you a big heads up where to look if there is any issues, CO and HC give the biggest clues.

follow that with a full compression test as mick suggested, making a note of max compressions and how many engine strokes it takes to reach that point.

[YnyrCymru]

First of all thank you very much for all of your replies!

Steff123-I did haver a new coil pack 6 months ago, so I might be idea to give that change. The case with piston rings is that its only done 75,000,abit low for the rings to go don't you think? But one of my mates did think the same, and it could be a solution.

artscot79-Yes I know but there's more soot than normal cars on it and it would back the fact that the car is running rich? A lot of people have suggested that they are pre measured at the wrong gap so I might take them out to gap them properly. And with the cone filter I know the disadvantage but I really doubt it would do that much of a difference? And I did make one full tank run with panel filter and I was more the less same (roughly 26-29MPG)

Mick85-i may sound dumb but what's a dry and wet compression test? will check those sensors cheers.

wase16ll- I'm going to do and emissions test on it, hopefully that will answer a lot of questions and I could work from there

Thanks again for your replies I do appreciate it!!

[stef123]

First of all thank you very much for all of your replies!

Steff123-I did haver a new coil pack 6 months ago, so I might be idea to give that change. The case with piston rings is that its only done 75,000,abit low for the rings to go don't you think? But one of my mates did think the same, and it could be a solution.

artscot79-Yes I know but there's more soot than normal cars on it and it would back the fact that the car is running rich? A lot of people have suggested that they are pre measured at the wrong gap so I might take them out to gap them properly. And with the cone filter I know the disadvantage but I really doubt it would do that much of a difference? And I did make one full tank run with panel filter and I was more the less same (roughly 26-29MPG)

Mick85-i may sound dumb but what's a dry and wet compression test? will check those sensors cheers.

wase16ll- I'm going to do and emissions test on it, hopefully that will answer a lot of questions and I could work from there

Thanks again for your replies I do appreciate it!!

The mileage goes for nothing really, between 80k and 110k - when I got rid is where I was using silly amounts of oil.

[wase16ll]

wet and dry compression tests

dry....

plugs out, tester in place, disable fuel system (pull pump fuse or relay out) throttle fully open..carry out test

wet

after each dry cyl test, remove tester, squirt half teaspoon of oil down plughole, retest as above

if wet test improves the compression, sign of worn rings

[mick85]

Ok a wet compression test is usually performed if one cylinders compression is low if u add couple squirts of oil in cylinder an compression improves this indicates ur piston rings gone if it don't improve usually problem lies with valve the

[YnyrCymru]

Ok thanks will try that in the near future. I did and emission test on Friday and it passed without a problem. Also I put a Diagnostics Computer on it (Snap On Solus Pro) and went to the live data and did some readings, but I cant be sure what there supposed to be. Here are some that could help.

O2 Sensor (Bank 1,before Cat) (mV)-563

O2 Sensor (Bank 1,After Cat) (mV)-5

Injection Time Bank 1 (ms) -3.3

Cylinder Head Temperature (V)-0.60...........This ones seems dodgy to me? Engine idling about 1000 RPM

Cylinder Head Temperature (V)-3.58 Engine RPM on 3000

Injector 2 Output Fault-Its switching between YES and NO all the time while the other 3 Injectors are Fine.

A lot of Data I know but I want to know your verdict gentleman.

Thanks again!

[wase16ll]

what were the emission readings...(passed as in mot standard or passed as in very good...big difference)

and did you carry out the tests throughout the range..ie..as i suggested earlier?

if the CO/HC etc were good then that basicly means the engine managment is good and the fuel entering is getting burnt not being thrown into exhaust...would question what you could do to improve fuel economy if all is working as it should, beyond being lighter on your right foot

agree some of the live data seems odd, but if CO/HC etc are what they should be, then cant see a problem with injector or temp sensor..both will have major effect on emissions.

[mick85]

Go back to basics bud a compression test will tell u so much more a lot them live data thing ain't a great help an u said emissions all good you could test injectors with multimeter an possibly swap 2 wit one do live data again an see if it changes when re do test also test temp sensor with multimeter from cold to warm

[AJRTDDI]

Compression test will tell you everything you need. if you was more local I'd do it for you.