Menu
What's new
By:
Advanced search...

Poor Fuel Consumption on 2.4 Auto

Absolutely true, all OBD tools read engine ECU codes.

Some OBD tools do a bit more and have a better "man-machine" interface, cloned HDS does a lot more but is not easy to set up or use (because it needs a laptop) but it has a good display capability
 
Thanks! Maybe in the future when I am gain some more knowledge I will invest in a cloned HDS.
 
Oh, are they that expensive. I will just stick with the normal OBD tool then.
 
I run dash command on my iPhone via a wifi dongle.

I normally use it for tracking fuel economy, but it'll show loads of parameters live, but these are of course only relevant if you know what you're looking at.

http://youtu.be/HCsVYmIgMeQ

Works in anything with an OBD2 port too, so it's pretty handy.
 
I've got an OBD reader app and a bluetooth OBD connector. Total cost was about £10 as the app is free. That'll sort you out to get the ball rolling.
 
Danny, it also depends on your phone. Android stuff prefers a Bluetooth dongle, iPhones a Wifi one.

As Steve says, you can get free apps if you just want to read codes.
 
I think maybe I will stick to the OBD reader for £14. It also explains in detail what the codes mean, so that will be useful. I hope it will come by Wednesday and I will plug it in and see what comes out. My phone is also on it's last legs so is not very reliable.
 
ref MPG, the most accurate way to read this is fill tank to top, reset mileage counter to zero, drive till empty, refill tank, take note of no of litres filled, divide by 4.546 = no of gallon used. Divide total miles covered on mileage meter by gallons = MPG

The reserve light is a guide only as sometimes when i refill at reserve light up the difference can be a good few litres.
 
f2raf said:
ref MPG, the most accurate way to read this is fill tank to top, reset mileage counter to zero, drive till empty, refill tank, take note of no of litres filled, divide by 4.546 = no of gallon used. Divide total miles covered on mileage meter by gallons = MPG

The reserve light is a guide only as sometimes when i refill at reserve light up the difference can be a good few litres.
Click to expand...
THERE IS AN ECHO IN HERE!!
 
edgeoftime said:
THERE IS AN ECHO IN HERE!!
Click to expand...
As an example

Lets ***ume 480 miles were covered on the mileage meter at the expense of 53.5 litre fillup, that is 11.78 gallons of fuel, thereby giving 40.74mpg
 
Danny, it's worth noting that the half way marker on the fuel gauge is not actually a half way indicator for fuel consumption. I think the tank must be narrower at the bottom than the top. Generally I get about 350-400 from a tank but always I'm at about 225-250 when I'm at the half way marker and then the consumption just drops off a cliff! The second half of the gauge are pretty exponential :rolleyes: .

Therefore, if you're going to make MPG calculations, best to do it from a full fill to fuel light coming on (which is 55 litres I think - 10 litres in reserve - I could be wrong, it could be 5 litres in reserve, double check the owner's manual). That will give you the most accurate indication.

Mine's manual by the way, so don't expect to get anywhere near what I'm getting in terms of economy. My mate's dad had a 2.4 auto saloon and round town he never got better than about 21-23 mpg. Obviously motorway and A road was high 20s, even low 30s on a very long cruise. But generally not great.
 
f2raf said:
As an example

Lets ***ume 480 miles were covered on the mileage meter at the expense of 53.5 litre fillup, that is 11.78 gallons of fuel, thereby giving 40.74mpg
Click to expand...

Stevearcade said:
Danny, it's worth noting that the half way marker on the fuel gauge is not actually a half way indicator for fuel consumption. I think the tank must be narrower at the bottom than the top. Generally I get about 350-400 from a tank but always I'm at about 225-250 when I'm at the half way marker and then the consumption just drops off a cliff! The second half of the gauge are pretty exponential :rolleyes: .

Therefore, if you're going to make MPG calculations, best to do it from a full fill to fuel light coming on (which is 55 litres I think - 10 litres in reserve - I could be wrong, it could be 5 litres in reserve, double check the owner's manual). That will give you the most accurate indication.

Mine's manual by the way, so don't expect to get anywhere near what I'm getting in terms of economy. My mate's dad had a 2.4 auto saloon and round town he never got better than about 21-23 mpg. Obviously motorway and A road was high 20s, even low 30s on a very long cruise. But generally not great.
Click to expand...



guys, we've been through all of this on the first page of this thread

The OP is now using the method described below (originally posted in #17 page 1)

In #43 his last calculation of 18 mpg was based 152 miles when he re-filled to the brim again (37.3 litres, 8.21 gallons)

Reason that he re-filled at that point is because it had taken him 11 days to do 152 miles i.e. he is only doing 14 miles per day (on average) or 5,000 per year ....so it's will take him over 2 weeks to do the "brim to orange-light", which is not necessary as long as he fills "to the brim" (click off) each time at the same pump.


This thread is in danger of becoming circular, hence John's remark in #161






freddofrog said:
As mentioned by several people already, the only way to measure mpg properly is by filling the fuel tank until the handle on the pump clicks off, then zeroing the trip meter before leaving the filling station.

Then drive the car until the tank is close to the empty light (whether the light comes on or not), go back to the same pump and refill until the handle on the pump clicks off.

Now go and pay and ask for the receipt. Work out the mpg from the miles on the trip meter, and the amount of fuel on the receipt.

Reason for doing it this way is because it gives a more reliable average i.e. more fuel over more miles. You can even do it several times i.e. write the miles onto the receipt that were on the trip meter, then reset the trip meter, etc, etc.

Also, the heavier an engine is, the more thermal mass it has, so it takes longer for the entire thermal mass to reach full temperature, and until that happens, the engine has not reached max efficiency. So if you drive a 2.4 Accord to a supermarket that is only 2 miles away, and then drive back home, your mpg will be appalling for that single trip. But combine it with a 1-hour motorway drive on cruise at 70mph, and the combined mpg will be vastly improved.

Tyre pressures also make a difference.

Finally, the tracking on the saloon needs a 4-wheel alignment, the Tourer does not.

edit: and this time of year the mpg is worse on all cars in the northern hemisphere
Click to expand...

freddofrog said:
mpg = miles-on-trip-meter ÷ litres-on-receipt x 4.54

e.g. 388 miles on trip meter, 48.39 litres

mpg = 388 ÷ 48.39 x 4.54 = 36.4


edit: there's also a revolutionary device called a "pencil", which can be used to "write" numbers onto the receipt :eek:
Click to expand...
 
To be honest 14 miles a day in a 2.4 auto... is high teens mpg really that major an issue?
 
I do kind of agree ;)

(might not be the engine, might only need a 4-wheel alignment)

Let's see if an OBD reader shows anything
 
At 14 miles a day, I wouldn't care what mpg I was getting.
 
^ too much for me, but I have built myself a de-restricted electric bike (250W) that does 20 mph, I could easily use that at 20 mph for 14 miles on one charge ....though it has to be said, cycling on roads in the uk is horrible (I spent 3 years in The Hague, cyclists' paradise over in Holland).
 
Ive done a fair bit of driving over christmas, to the west of Ireland and back to southampton.

1180 miles or so used and about half a tank left in my car, I put in 214 litres.

mpg would be about 27mpg using the formula above, give or take.

some terrible roads (and drivers) in Ireland ffs, wont be going back in a rush.

20160106_053522.jpg
 
Still waiting for the OBD2 reader, but was just wondering when is the best time to plug the OBD2 reader to the car for the most accurate readings? Should I drive the car for a while until it reaches operating temperature and then plug it in, or is it sufficient to just leave the engine on and plug in straight away whilst parked?
 
It'll read all the time. I use mine to monitor fuel consumption, so it's on all the time.

Depending on which program you use with it, you can do much more than just read and clear fault codes.

I keep tabs on everything, so I know what the effect of all the little mods I do have on fuel consumption. This was my journey home tonight.
Seems I've gained a couple of mpg by going back to an OE air filter on the diesel.
Economy changes noticeably depending on what fuel I use, and wether or not I use an additive, tyre pressure, remap, fuel injector refurbishment, suspension setup etc.
Without monitoring these things, I'd never have worked out what it likes best. It's gone from returning 37mpg average when I bought it, to the point where it's averaging 48-50 over the same mixed journey at the same speed this last week.



 
In addition to reading the codes, I want to check the live data figures e.g emissions, lamda sensor readings (if possible) e.t.c, so was thinking it would be more accurate to get the reading once the car is at operating temperature rather then plug it in when cold.
 
Plug it in at the start of the journey and monitor it, so you see how it works in all situations. Some faulty components can fail when hot, others improve with heat yet are ok cold.
 
danny35 said:
In addition to reading the codes, I want to check the live data figures e.g emissions, lamda sensor readings (if possible) e.t.c, so was thinking it would be more accurate to get the reading once the car is at operating temperature rather then plug it in when cold.
Click to expand...

Goodluckmonkey said:
Plug it in at the start of the journey and monitor it, so you see how it works in all situations. Some faulty components can fail when hot, others improve with heat yet are ok cold.
Click to expand...

Unfortunately the one that Danny has bought http://www.ebay.co.uk/itm/221966699147 does not have the screen or the processing power to do anything like the apps on a smart phone. A smart phone is a small version of an ipad, and an ipad is a small version of a laptop i.e. a smart phone has both the processing power and the screen to be able to compute and display information in many ways, based on receiving and extracting several pieces of data out of a live data stream from a wireless OBD device.

Although the ebay one says "View live data stream" I wouldn't raise my expectations too high on what it will display.
 
freddofrog said:
Unfortunately the one that Danny has bought http://www.ebay.co.uk/itm/221966699147 does not have the screen or the processing power to do anything like the apps on a smart phone. A smart phone is a small version of an ipad, and an ipad is a small version of a laptop i.e. a smart phone has both the processing power and the screen to be able to compute and display information in many ways, based on receiving and extracting several pieces of data out of a live data stream from a wireless OBD device.

Although the ebay one says "View live data stream" I wouldn't raise my expectations too high on what it will display.
Click to expand...
If the ebay device doesn't show live date, I wil probably purchase the torque online app and use the cable provided with the ebay OBD2 device to connect to the car.

If you read from 4.4 on the instruction manual in the link below, it provides more information on what live data feeds it has.


http://avto-adapter.ru/download/D900_CANSCAN_MANUAL-V1.30.pdf
 
Sounds like a good idea. From what I've heard, the torque app's a decent bit of software.
 
danny35 said:
If the ebay device doesn't show live date, I wil probably purchase the torque online app and use the cable provided with the ebay OBD2 device to connect to the car.

If you read from 4.4 on the instruction manual in the link below, it provides more information on what live data feeds it has.

http://avto-adapter.ru/download/D900_CANSCAN_MANUAL-V1.30.pdf
Click to expand...
This is what it says in the PDF

VIEWING LIVE DATA
1. Select Live Data from the main menu.
2. Real-time Live Data (PID) information supported by the vehicle
under test displays. Remember, what you are viewing is "real-time" Live Data. The
values (volts, rpm, temperature, vehicle speed, system status etc) for
the various PIDS displayed may change as the vehicle's operating
conditions change.
3. A vehicle usually supports several PIDs, however, only a limited
amount of PID data can be displayed on the screen at one time. Use
the the UP and DOWN buttons, as necessary, to scroll up or down
to view all available PID data.

The display on the device is the issue, it only has a few lines of text.
The other issue is that there is a difference between "data" and "information".
"data" = numbers, "information" = a computation involving data.

e.g. MPG (information) = miles (data) ÷ litres (data) x 4.54

so there is no way that you will get, say, MPG from that OBD device

Also, the "apps" that you download are specific to smart phones. The cable that comes with the OBD device is not going to plug into a smart phone. To use a smart phone with an app to display information and/or raw data, you need a wireless OBD device that is suitable for the smart phone that you have.
 
Okay, thanks Brian! Well I might as well try it now that I've ordered it and see what happens. If it detects the error code or gives me any information that solves the issues that I am experiencing it will be worth the money. I have read that it displays Lambda Sensor details which is useful, if the problem is with the injectors then I am not sure it will be of much use.
 
You must log in or register to reply here.
Top