Fuel Economy

Hi all,

So last weekend when I picked up my puma I got a full tank of petrol then drove 60 miles to Essex to get a manifold and exhaust fitted. When I got there the fuel level was just under full. After the exhaust was fitted and driving back the same 60 mile distance when I got home the needle was at 3/4 full.

It's got me slightly concerned that this is drastically affecting my fuel economy. The lambda sensor wiring weas extended and he plugged in something to the passenger footwell plug to ensure it was working correctly.

From a full tank I got about 300 miles. About 40% of the time during I was thrashing the car. So I filled her up again yesterday and i'm just under 70 miles now and the tank is at 3/4's and i've literally driven like an old woman changing gear at 2-2.5k and never going over 55 mph to see what fuel economy I can get. Yet when I first drove the car I got 120 miles before the needle was around 3/4's.

Should I be concerned? I can't remember what fuel economy I was getting from my first puma but the change seems drastic since fitting this manifold and exhaust.

Ed

I've always found the Puma fuel gauge to be quite inconsistent.
You will find that one part of the tank will seem to empty quicker than another, making it seem it's economical one minute but not the next.
Had you have filled the tank back up on the return journey, you may have found it could have used the same amount of fuel?

Thanks for the reply. I did wonder this but wasn't entirely sure. Well i'm going to go down to when the fuel light comes on as this is when I filled up yesterday. So long as it gets over 325 or so miles then I guess I know it's not the recent add on that's causing the problem.

Still, it's not as strange a smy Saab's fuel guage. That used to go down then you'd get out and come back in the next day and the fuel guage will have jumped up by 1/8 or more.

Cars can be very confusing.

Ed

My old Puma was the other way round. I'd do a journey and think the economy was really good, just to start it up the next day to find I'd actually got almost quarter of a tank less!

267 miles from a full tank whlist driving like an old person 90% of the time. Surely that's far too low?

Ed

Sounds low but then figures do seem to vary, is that to the light or including some on the light?

Up to the light on. I checked other posts here. People getting just over 400 driven sensbily. I'm quite concerned now. SO I had the exhaust changed and he extended the lmda sensor. Surely an exhaust/manifold mod couldn't be causing such a drastic hit to fuel economy?

Ed

400 isn't the norm - somewhere about 300 to the light would be considered normal / light use of the right pedal.

Hmm that's slightly less worrying then. My friend at work who's a car nut said I should get it remapped to help with the fuel economy.

Ed

As it's a non turbo car, a remap won't help that much in terms of MPG.

(Or power for that matter)

Are you aware the Puma’s tank is only 8.8 gallons?

From the extensive real-world mpg data from http://www.spritmonitor.de/en/" onclick="window.open(this.href);return false; you can expect to average 36.5mpg, or there abouts. So that’s an average range of 300 miles, leaving only half a gallon left.

Indeed I used to get about 300 to the light.

I can say that in owning 3 Pumas I never once saw 400 miles from a tank!

I was pleased if I could keep the reserve at bay until 320.

Thanks a lot for the replies guys that's really helped put things into perspective. I was really fretting about it. I might hold off on the remap for now then as I intend to buy an Emerald ECU when I get throttle bodies fitted at the end of the year.

Thanks again for the replies

Ed

-B- said:

Are you aware the Puma’s tank is only 8.8 gallons?

From the extensive real-world mpg data from http://www.spritmonitor.de/en/" onclick="window.open(this.href);return false; you can expect to average 36.5mpg, or there abouts. So that’s an average range of 300 miles, leaving only half a gallon left.

Click to expand...

You'll also find Cherie's Millennium on that list at 42mpg and she didn't hang about.

http://www.spritmonitor.de/en/detail/407790.html" onclick="window.open(this.href);return false;

Impressive, Dal

Can you buy bigger tanks for the Puma?

-B- said:

Impressive, Dal

Can you buy bigger tanks for the Puma?

Click to expand...

Why would you want to do that? It's not like fuel stations are a rare sight on our roads?

fairlight said:

-B- said:

Impressive, Dal

Can you buy bigger tanks for the Puma?

Click to expand...

Why would you want to do that? It's not like fuel stations are a rare sight on our roads?

Click to expand...

Why don’t we all use 2 gallon tanks then? Petrol stops = time = money.

Besides, the less time I spend mingling with the great unwashed (and Mackie D chavs at my nearest station) the better :x

Because 2 gallons would be silly, but a near 9 gallon tank on a small car giving a range of 300 miles is not too bad, I would want one stop between my house and lands end for a pee and stretch me legs,
How long does.it take you to slosh some fuel in? In 20 years of driving cars and motorcycles I have never thought Christ, I'm wasting my life away in a fuel station....

Fine, that’s your life you’re wasting. Some people, if not the majority of people, would prefer to waste less of their life at fuel stations, hence why a longer range is preferable. :roll:

If you wanted to be really picky....
Smaller fuel tank = less weight when full = higher economy = less cost.

So you're larger fuel tank would sacrifice economy for range. You can't have the best of everything.