NewHilux.net

Good morning all,
Any one have any idea as to why my fuel consumption would have increased dramatically? - measured as litre's/100km.
** A little history first **
- I have a 2016 SR5 auto, had a remap and 3inch exhaust last year and fuel economy went down from 10.7 avg to 8.5 avg, loaded up or highway
- Recently installed ARB Frontier long range tank and fuel economy didnt change - stayed around 8.5
- Just had 90k service with a new steel bar and winch fitted with new front rotors and pads
- Car now seems a little rough at idle or just off idle (when rev's are coming down stopping at lights etc)
- Otherwise no other noticeable change other than economy going back to 10.5 ish.

I have no idea and before I take it back to my mechanic I was hoping to maybe get some idea or check a few basic things.
Would a re-map disappear??? and reset to factory ???'Surely the bar and winch wouldn't impact that much ???

Thanks for any suggestions. Simon.

Ever wondered if the last service the dealer'remapped' your remap? I see you considered that, it may be the case, they don't just 'return' to OEM tune. The dealer may have disconnected the battery but that wouldn make the remap 'disappear'. Oh, just thought, how are you measuring your economy? If the dash readout was reset that may give you the answer.

Another possibility is that the service included diagnostic which may have uncovered some anomalies in the data so they refreshed the ECU. They may do this because there was a suspicion of a remap and rather than accuse you they just reset the ECU.

A dealer will often load up the latest Toyota ECU tune unless told not to. I’ve had to just about put a gun to the head of the service dept to stop them doing mine.

Good chance they’ve wiped your remap.

G'day Gipsy and ggreenie,

Luckily I have not been to a dealer since warranty expired. The current mechanic is the one who arranged the remap and also serviced the car since warranty ran out so pretty sure he has not "changed" anything. I will check though.
Battery was disconnected for winch install but as you mention shouldnt have changed anything.
Fuel economy is measured by dash readings and actual fuel in/km driven, luckily for me the dash reading on mine is very accurate and I keep an eye on this all the time.
I have driven 1500kms since the service at the old economy level ?

** Possible air flow problem ?? Air filter not in correctly or dirty MAF sensor ?? **
I could check these tonight.

Thanks for the feedback.

How often do you reset the dash reading? Does it correspond to a manual calculated figure? Fuel Bowser's are notoriously inaccurate so is it the same fuel station? I check mine at every fill both manually and via the dash readout. But the manual figure must be done at the same fuel station because the angle of the driveway alone can make a big difference. Also using the same fuel station gives you a degree of protection from contamination but never fill up if there's a tanker dumping fuel at the service station. Also different fuel brands have variable additives, cetane rating etc which may affect the performance/consumption. Biodiesel increases consumption, and the supplier isn't obliged to tell you if it's in there! Check your water trap in the filter, contamination is possible. Fit a pre-filter so you can check the bowl often.

Also it may be worth changing to litres/100 km to check fuel consumption. Simple math is litres in/hundreds of Kilometers travelled i.e. if you put 100 litres in and travel in 1000km (1000 km equals 10*100 its 10ltr/100 km.) Easy as!

Cheers Gipsy,
Dash is reset each tank and corresponds to manual figure.
Fuel from same Caltex each time. Never biodiesel.
Pre-filter all clean, check that each fill.

I am a bit mechanically inclined (and a bit anal with checking the car and listening for odd things) and this has me stuffed, probably something simple but I am out of ideas.

Thanks Simon.

http://www.petrolcostcalculator.com.au/ ... er-100-km/

I would be checking vacuum hoses and MAF sensor to start with.

Thanks Grunf,

Will check the hoses with the MAF when I get home.

Cheers.

Did they do a wheel alignment after fitting the bar and winch? That would make the front sag a fair bit, especially on a vehicle with 90K on it... if the alignment is fair bit out, it could explain the usage, and the extra weight added combined with braking will put a fair bit of downforce on the front end and pressure through all the components underneath, could be that it's actually other things feeling rough and not the motor.
Can you see visible scrubbing on the tyres?
Mine certainly felt different after just putting a steel bar on. Haven't done an alignment as my plan was to put winch and sliders on, then get new suspension to deal with the load. My fronts are scrubbing pretty badly on the outsides, but still OE tyres so not disappointed about replacing them sooner.

Skeb wrote:Cheers Gipsy,
Dash is reset each tank and corresponds to manual figure.
Fuel from same Caltex each time. Never biodiesel.
Pre-filter all clean, check that each fill.

I am a bit mechanically inclined (and a bit anal with checking the car and listening for odd things) and this has me stuffed, probably something simple but I am out of ideas.

Thanks Simon.

Simon, it's always difficult about Biodiesel but unfortunately the fuel companies are not required to tell us if bio is present. Almost all diesel fuel has bio, up to 10 percent but some have more than others. The imported stuff (mainly from independent outlets) comes from South East Asia and is mostly straight diesel, but you never really know.

Cheers for the comment witherz,
The front dropped 14mm each side, do have OME suspension but not rated for steel bar and winch, will need to upgrade the springs at some point.
Tyres were rotated but no wobble/ scrubbing noticeable.
The roughness is really noticeable at that end point of braking just before stopping (like rough idle), with the service work I had done (brakes etc) it could be something else in the front end, will have the mechanic look it over.
Cheers.

Skeb wrote:Luckily I have not been to a dealer since warranty expired.

Well... I’m out of ideas.

Back to the mechanic if it was me.