Suggestions for better mpg please.

singist

singist

singist

Soldato
Joined
18 Oct 2002
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Student Hell Headingley
I'm old and don't go around in race mode anymore so am a bit worried about my consumption, or rather, the consumption of my Saab 93.

I have just fitted a brand new turbo and don't know if that needs tuning, or if things could be improved some other way or both; your ideas are most welcome.

Engine is a 205E 2ltr petrol turbo and I'm doing just less than 20mpg on the short runs that are my norm (4miles x 3 or 4 times a day)

I don't have much spare £ at the mo' so spending a few quid on some sort of analysis/tuning might work out economically; I just don't know exactly what sort of thing I should be looking for.

I don't expect to get marvelous figures, given my short journeys etc but think that less than 20mpg for a "family" car is a bit grim.
 
New turbo shouldn't need tuning so to speak, just the boost setting to the correct level. If it is currently overboosting and has closed loop lamba control then it is possible the ECU is throwing in a silly amount of fuel to compensate. I don't know if your Saab will have closed loop control. Also have you checked the pressure side of things for leaks? The turbo may well be producing a lot more than the required boost just to feed the correct level to the inlet if you are leaking presssurised air to the atmosphere.

Think the short journeys will also have something to do with it, as the car will only just be getting warm when you turn it off again.

Take it to a specialist for a set up. This will cost £120-£150, but if it saves your engine which certainly doesn't sound like it is performing correctly, its money well spent. Money well spent anyway really.
 
20mpg from a 2.0 Turbo doing short journeys around town doesnt seem too wrong to me. I used to get 24mpg from a 2.0 non turbo in the same circumstances at this time of year.
 
Keep it below 3k revs - you say you don't race so this shouldn't be a problem :)

I've noticed in mine when doing motorway journeys or around town keeping it below 3k revs saves my consumption a lot.

Taking it over 3k and the turbo really starts to kick in and the fuel gauge goes down faster than a hookers underwear.

I normally average 26 - 30mpg in general use and I have the same car. (1999 model) On the motorway, following the above rule I'll get 35ish - managed 35.7 on the way to the RR

Hope this helps!
 
I just "tootle" nowadays and don't let the engine labour but it still seems thirsty.

Thanks for the suggestions so far.
 
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