[Karl702123]

Hi all.
I have a 156 2.5 V6. Currently getting around 13 - 14 mpg. Surely I should be doing better than that? Before anyone suggests it... I don't always have a heavy right foot - although it is fun! I have had my engine recently tera-cleaned (which I highly recommend) and that improved this mpg by around 3mpg. The temperature gauge doesn't rise to 90 unless I'm at standstill but I have replaced thermostat and temperature sensor. I'm at a bit of a loss now as to unusually high fuel consumption. Has anyone got any suggestions?

 

[WADEY]

You should be getting 25-32 mpg really. Fuel leak? Sticking brake caliper? Mass air flow can affect fuel consumption I seem to remember.

 

[WADEY]

Temperature gauge on all Alfas seem to sit at 70 C unless you are in traffic. I think it's a live read out, as apposed to average temp on most manufacturers.

 

[Karl702123]

My rear brakes are new - including handbrake cables. I've tried 2 different MAF sensors - both made no difference. Scratchy head / frown time...

 

[Karl702123]

There is no sign of a fuel leak as far as I can tell. No smell of petrol or tell tale marks on the ground.

 

[WADEY]

Is that 13mpg on trip computer? Or have you worked it out?
Does it sound as though it's running right?

 

[Karl702123]

That's what the display reports. If my calculations are correct, I can do around 300 miles on a full tank which equates to approx 22mpg. Is there any way to reset the display calculations? Probably just part of the rich experience of owning an Alfa?

 

[WADEY]

Press the centre button of indicator stalk to get 'trip A' on display, then long hold of button to reset 'trip A'.

 

[Karl702123]

Thanks Wadey. I'll give that a go...?

 

[Chris M]

My 3.2 V6 currently shows around 25 mpg, so you should be getting around that at least in general driving (less if you do a lot of short journeys)....

 

[kandlbarrett]

I don't know the relationship between the 156 and 75 2.5 V6 but my 75 (no longer have it now) used to do 28-30 driven relatively sensibly (31 - 32 on a long sensible run) and 25-27 driven hard.

My process would be:-

1) have the codes cleared; drive the car; re-read the codes and if there are any work with those. Not all fault codes cause the engine light to illuminate.
2) check for exhaust leaks.
3) check condition of air filter.
4) check for leaks on the inlet pipes.
5) check spark plug colours. What colour are they and are they all the same or very similar.
6) compression test - just to check general engine condition.

 

[Keithy]

Only do fuel consumption based on tank to tank readings.

This is what mine did.

http://www.alfaowner.com/Forum/alfa...stic-156-v6-fuel-consumption.html#post3711013

Getting less now I have changed to the GTA.

 

[115686]

How long are your journeys, and over what roads?

On my old 32 mile, each way, commute on the M4 (so about 70 - 80), I'd get 330 or 360 miles on a tank. Best ever was 400. Now, commuting into London, 300 is good, normally about 250.

 

[rgwm]

Brimmed ours before setting off for Spring Alfa Day - normal motorway / A-road driving at about 70 - 80ish cruising, with a few spells of 50 average speed cameras, then a fair bit of running around Bournemouth area and a crawl into and out of SAD, refueled as on the warning light after 386 miles = 30 mpg. Happy enough with that. 300 or so miles back home with some fairly gentle running through smaller roads before joining M5 South of Gloucester saw the gauge not far below the halfway mark.....it does tend to drop fairly sharply once below the quarter mark, though!

 

[Sam bailey]

I get approx 24-30mpg (working it out) and just under 400miles from a full tank...driven gently:devious:

 

[chrishendrix]

The info centre figures are at best inaccurate.
Working out consumption from brim-to-brim re-fills and mileage readings I get about 21mpg in town, 30ish on a long run.
Temp gauge usually sits just below 90 with aircon on, 90 without.

 

[swazi_123]

All depends on the traffic and average speed. I have found all Busso powered Alfas return horrendous fuel consumption figures in any stop start traffic situations. On motorway, dual carriageway though, they can be very reasonable. I get 31 mpg on a run in my 3.2 GT and got slightly better with my old 2.5. Driven in an urban environment though, they drink the stuff, especially short journeys when they barely get up to temperature.

 

[Shimmerydolmeo]

All depends on the traffic and average speed. I have found all Busso powered Alfas return horrendous fuel consumption figures in any stop start traffic situations. On motorway, dual carriageway though, they can be very reasonable. I get 31 mpg on a run in my 3.2 GT and got slightly better with my old 2.5. Driven in an urban environment though, they drink the stuff, especially short journeys when they barely get up to temperature.

Could this explain why I only get 150 miles out of a tank when driving my 3.2 GT on urban runs (I live 0.5 miles from work!). Got 275 miles on a motorway trip, that included a few spells of taking her to 150mph.

 

[scottyf]

Yep through peak hours my 2.5 would return 22mpg in urban conditions.

Motorway high twenties.

loved that engine.

 

[Shimmerydolmeo]

Does anyone know the size of the GT 3.2 fuel tank and how much is left in when the warning light comes on?