Suggestions to improve my poor fuel economy

LIFTED · Post by **LIFTED** » Fri Sep 30, 2011 5:33 pm

I bought a can of Subaru UEC from Subaru in Wangara, I followed the instructions and was very disappointed, no huge plumes of white smoke came out!!! maybe a couple of tiny little puffs. So I thought maybe it didn't dislodge anything and went back and bought another can and put this through, again still no white smoke and the car doesn't feel any different to drive. Other people on other forums rave about this stuff. Maybe the engine was already pretty clean, must have been well looked after before I got it

mud_king91 · Post by **mud_king91** » Fri Sep 30, 2011 5:54 pm

hydrogen hybrid conversion ?

YouTube · Post by **El_Freddo** » Fri Sep 30, 2011 7:18 pm

mainbreak wrote:I bought a can of Subaru UEC from Subaru in Wangara, I followed the instructions and was very disappointed, no huge plumes of white smoke came out!!! maybe a couple of tiny little puffs. So I thought maybe it didn't dislodge anything and went back and bought another can and put this through, again still no white smoke and the car doesn't feel any different to drive. Other people on other forums rave about this stuff. Maybe the engine was already pretty clean, must have been well looked after before I got it

One can is enough.

This is all that I got from using the UEC can:

As you can see, not a lot at all. Very disappointed with this. But I'm happy with the results. I think my engine was already clean internally as it's a country car so it's getting a good run and the crankcase ventilation system is breathing well, plus it's running at temp for periods of time rather than getting up to temp then shutting down like a lot of cars seem to in city conditions...

Cheers

Bennie

Post by **TOONGA** » Fri Sep 30, 2011 8:36 pm

mainbreak wrote:I bought a can of Subaru UEC from Subaru in Wangara, I followed the instructions and was very disappointed, no huge plumes of white smoke came out!!! maybe a couple of tiny little puffs. So I thought maybe it didn't dislodge anything and went back and bought another can and put this through, again still no white smoke and the car doesn't feel any different to drive. Other people on other forums rave about this stuff. Maybe the engine was already pretty clean, must have been well looked after before I got it

I was expecting a big cloud of smoke as well

but hey my car was used for long runs most of the time the shortest trips were normally 40km

the other alternative is a 5 speed dual range gearbox

that will improve your economy a little

TOONGA

LIFTED · Post by **LIFTED** » Sat Oct 01, 2011 12:36 am

El_Freddo wrote:One can is enough.

This is all that I got from using the UEC can:

As you can see, not a lot at all. Very disappointed with this. But I'm happy with the results. I think my engine was already clean internally as it's a country car so it's getting a good run and the crankcase ventilation system is breathing well, plus it's running at temp for periods of time rather than getting up to temp then shutting down like a lot of cars seem to in city conditions...

Cheers

Bennie

That's a lot more than what I got

SUBYDAZZ · Post by **SUBYDAZZ** » Mon Oct 03, 2011 7:40 pm

mainbreak wrote:I couldn't find any flash lube so I bought some Nulon injection cleaner and put this in my tank for the first 100km distance no change then today after about 130km distance of driving I noticed while on the freeway my revs are lower! Unbelievable !
At a constant 100km/h the revs used to sit at 3000 now they sit at 2750
and for 90km/h the revs sat at 2750 now they sit at 2500
and for 80km/h the revs sat at 2500 now they sit at 2250
I've finally found and bought some flash lube and will use that after this Nulon stuff runs out.

Unbelievable, yes, unless you were in a different gear, or also changed a gearbox or final drive ratios. Or, for some reason you had a slipping clutch before, but as you say this is an auto isn't it? For any given wheel speed, and there fore indicated speed on the dash (not ground speed as this varies by tyre circumference) the gearbox must be turning a certain known speed in a given gear, or unless you have a CVT gearbox.

Just 2 questions re: your vehicle, how many km on the EJ22 and what size tyres are you running.

It's quite fine to run your tyres 10-20% over the placard rating and you should get slightly better economy. 40psi is pretty harsh on a lot of roads though. Just also check the max pressure (if stated) on your tyres too.

I've done extensive scientific fuel economy testing on my 92 Liberty EJ22 wagon (over a quarter of a million kilometres actually) over several years with several fuel types and I can tell you for a fact, on my vehicle the following applied: normal unleaded was by far the most fuel efficient fuel to use, it was better in mileage and cost terms compared to E10 unleaded, 95 premium and 98 premium. Some engines may perform better on the higher rated fuels and while mine definitely felt more responsive it also used more fuel.

I would be happy to share my research (Excel spreadsheet) for anyone that's interested, there's a lot of info on there.

A really brief summary is here:

Year......L/100km...mileage
2002.....10.31.......38818
2003.....10.39.......36906
2004.....10.89.......34488
2005.....10.50.......35336
2006.....10.65.......27957
2007.....10.74.......32405
2008.....10.82.......18444
2009.....10.74.......20202
2010.....10.82.......11125
Overall..10.60......255681km
Best......8.32 (at least 200km for the tank)
Worst....14.18 (at least 200km for the tank, not towing)

I'd expect autos to use a bit more fuel or if you're carrying around a lot of weight or towing too obviously. Roof racks and bullbars will also add significant drag (mine had a light bullbar most of it's mileage) which in turn adds to fuel used.

Based on the research I've done I'd say it's is absolutely normal for that model to use between 10-11L/100km.

Two additional tips for ACCURATELY measuring L/100km are:
a) Try not to refill until you've used at least half a tank, and preferably pretty close to a full tank (50+L) as the error gained from uncertainties are less and you don't get a bias error for the weight of fuel you're always carrying around if you're filling up every 100-200km or so.
b) When you fill up you must fill until there is fuel visible in the filler neck to ensure it has taken (near enough) the exact same amount of fuel each time. This can be a bit tedious depending on the pump, but after the first "click" you can sometimes get as much as 10L more fuel in. It helps if you always use the same servo or pump to eliminate variance from the evil dodgy-calibrated fuel pump delivery which tends to be less accurate, at least anecdotally with lower amount of fuel (so the servo gets more cash by the pumps saying they deliver more than they actually do) actually dispensed, than what it says, though many people think that this doesn't happen any more...

LIFTED · Post by **LIFTED** » Tue Oct 04, 2011 12:54 am

SUBYDAZZ wrote:Unbelievable, yes, unless you were in a different gear, or also changed a gearbox or final drive ratios. Or, for some reason you had a slipping clutch before, but as you say this is an auto isn't it? For any given wheel speed, and there fore indicated speed on the dash (not ground speed as this varies by tyre circumference) the gearbox must be turning a certain known speed in a given gear, or unless you have a CVT gearbox.

Just 2 questions re: your vehicle, how many km on the EJ22 and what size tyres are you running.

..

Yes unbelievable I did take before and after pics But I just had a look on my phone and I must have deleted the before pics

they were taken a while ago. I took pics and measured the revs and speed on the same section of the freeway the only variable was the first higher reving measures were taken early in the morning on a cold day and the others were in the afternoon on a warmer day, here is most recent pic

Engine has 175000km and tyres are standard 185/70R14
Yes at 36psi I do find the tyres a bit harsh when I go over those steel speed humps in shopping centre car parks!

To do the consumption test I've been timing it so I only do 100km each time or close to say +or- 3km I then fill up at the same pump, I hold the nozzle on full bore and stop at the first click. 11.8 is the best I have got so far.
Yes please can you email me your fuel consumption info to sparklesigns(at)gmail(dot)com
Changing the plugs is next on my list, Ill do a separate post elsewhere for plug recommendations showthread.php?p=179689#post179689

SUBYDAZZ · Post by **SUBYDAZZ** » Tue Oct 04, 2011 1:54 am

mainbreak wrote:Engine has 175000km and tyres are standard 185/70R14
Yes at 36psi I do find the tyres a bit harsh when I go over those steel speed humps in shopping centre car parks!

Yeah, it depends how fast you hit them

mainbreak wrote:To do the consumption test I've been timing it so I only do 100km each time or close to say +or- 3km I then fill up at the same pump, I hold the nozzle on full bore and stop at the first click. 11.8 is the best I have got so far.
Yes please can you email me your fuel consumption info to sparklesigns(at)gmail(dot)com

Yeah, see what happens if you go a lot further and then calculate it, there are inherent errors when relying on the click method as it will click off at different levels every time, depending on the flow rate of the fuel nozzle, the temperature of the fuel in both tanks and the amount of air in the fuel as it's pumped. For a rough idea I guess it's OK though. You see what I mean about the fill to the filler neck method, if it's visible and not going down (as it will the first few times you try to trickle feed it until all the air has exited the tank) you can't argue that it's not *full*. However much fuel you fill with or distance you travel it's a simple as dividing the litres you fill it with by the kilometres divided by 100. eg:l 42L and 406km will be 42/4.06 = 10.435L/100km. It's not necessary to drive the same distance each time. The vehicle has a 60L tank too so you can get well below the empty mark / low fuel light before she's dry

Email is sent.

mainbreak wrote:Changing the plugs is next on my list, Ill do a separate post elsewhere for plug recommendations showthread.php?p=179689#post179689

What do your current plug tips look like? If your budget can stretch, consider a platinum or similar type plug that should not need to be replaced as often (usually up to 100,000km).

The other things I can suggest are replacing the O2 sensor (very expensive as a genuine part but about 20% of that as a Bosch aftermarket part. Additionally check your air filter isn't all clogged up.

LIFTED · Post by **LIFTED** » Thu Oct 20, 2011 12:47 am

SUBYDAZZ wrote:Unbelievable, yes, unless you were in a different gear, or also changed a gearbox or final drive ratios. Or, for some reason you had a slipping clutch before, but as you say this is an auto isn't it? For any given wheel speed, and there fore indicated speed on the dash (not ground speed as this varies by tyre circumference) the gearbox must be turning a certain known speed in a given gear, or unless you have a CVT gearbox.

Just 2 questions re: your vehicle, how many km on the EJ22 and what size tyres are you running.

It's quite fine to run your tyres 10-20% over the placard rating and you should get slightly better economy. 40psi is pretty harsh on a lot of roads though. Just also check the max pressure (if stated) on your tyres too.

I've done extensive scientific fuel economy testing on my 92 Liberty EJ22 wagon (over a quarter of a million kilometres actually) over several years with several fuel types and I can tell you for a fact, on my vehicle the following applied: normal unleaded was by far the most fuel efficient fuel to use, it was better in mileage and cost terms compared to E10 unleaded, 95 premium and 98 premium. Some engines may perform better on the higher rated fuels and while mine definitely felt more responsive it also used more fuel.

I would be happy to share my research (Excel spreadsheet) for anyone that's interested, there's a lot of info on there.

A really brief summary is here:

Year......L/100km...mileage
2002.....10.31.......38818
2003.....10.39.......36906
2004.....10.89.......34488
2005.....10.50.......35336
2006.....10.65.......27957
2007.....10.74.......32405
2008.....10.82.......18444
2009.....10.74.......20202
2010.....10.82.......11125
Overall..10.60......255681km
Best......8.32 (at least 200km for the tank)
Worst....14.18 (at least 200km for the tank, not towing)

I'd expect autos to use a bit more fuel or if you're carrying around a lot of weight or towing too obviously. Roof racks and bullbars will also add significant drag (mine had a light bullbar most of it's mileage) which in turn adds to fuel used.

Based on the research I've done I'd say it's is absolutely normal for that model to use between 10-11L/100km.

Two additional tips for ACCURATELY measuring L/100km are:
a) Try not to refill until you've used at least half a tank, and preferably pretty close to a full tank (50+L) as the error gained from uncertainties are less and you don't get a bias error for the weight of fuel you're always carrying around if you're filling up every 100-200km or so.
b) When you fill up you must fill until there is fuel visible in the filler neck to ensure it has taken (near enough) the exact same amount of fuel each time. This can be a bit tedious depending on the pump, but after the first "click" you can sometimes get as much as 10L more fuel in. It helps if you always use the same servo or pump to eliminate variance from the evil dodgy-calibrated fuel pump delivery which tends to be less accurate, at least anecdotally with lower amount of fuel (so the servo gets more cash by the pumps saying they deliver more than they actually do) actually dispensed, than what it says, though many people think that this doesn't happen any more...

OK after doing a few little mods I've managed to improve my fuel economy.
I've put through 2 cans of UEC
Oil and filter change penrite 10 50
new paper air filter
new spark plugs the old ones looked pretty good
Auto fluid and filter change and new front auto seal and rear engine seal Thanks to RSR555 for the auto removal and seal replacement oh and Toonga.
lastly a ceramic engine treatment.

I've been doing full tank testing
and now
with BP 91 around town I get 11.1 litres per 100km
with BP 95 around town I get 10.7 litres per 100km

(When I first got the car I was getting an average of 12.5 litres.)

coxy · Post by **coxy** » Thu Oct 20, 2011 10:39 pm

With any late model with a hot wire sensor,get a can of carby cleaner of electronics cleaner and keep the hot wire sensor clean they get a buildup of dust that covers and insulates the sensor throwing the mapping off as the look up tables that end up being used are for an engine running in colder conditions.
Now as anyone should know cold conditions means use the choke in a carby car or in the case of electronnic systems the cold run cycle hence more fuel use and often flat spots under load when accelerating.

fredsub · Post by **fredsub** » Sun Oct 23, 2011 9:14 am

here is some interesting reading http://www.enginebasics.com/Engine%20Ba ... Timing.htm l

i recall reading somewhere there that subaru engines are rather lax at tight
timing resulting in less than would should be possible performance/economy.

this here might be interesting http://store.crawfordperformance.com/store/products/566

something to think about the next time I plan to do the timing belts......

anyway, subaru's with AWD are never going to be the most economical cars
to drive on the road anyway. With our mostly dry and snow-free roads, AWD on the tarmac is highly overrated.