Technical 17mpg on Ciecento 1.1 (usually 50mpg) Help!!

[cheiron]

Replaced fuel line filter as originally running lean. Now uses petrol like there is no tomorrow! Tried replacing air filter, also replaced temperature sensor for injection system (the one with blue cap 2 leads near inlet manifold). Also replaced the temp sensor on block (this supplied incorrect as temp warning light glows in relation to temp when should be simple on/ off switch) -dont think this is the problem though. Otherwise goes very well performance great. Just ++++ fuel consumption...
Should i look at the ECU or is possible to reduce fuel line pressure??

 

[blu73]

double check around the fuel filter you changed, make sure its not leaking at all.

Can check the fuel pressure but i'd be suprised if that's the issue tbh.

 

[varesecrazy]

double check around the fuel filter you changed, make sure its not leaking at all.

Can check the fuel pressure but i'd be suprised if that's the issue tbh.

Ditto..!!,

I'd think leaks were the obvious thing,

11MPG that's REALLY poor, if it was just overfuelling I doubt it would run well,

RE -the temp sensors..unplugging one at a time may find the "limp-home "/default ECU setting improves things,

need more info for a full diagnosis..!! ( no warning lights -coil packs??),
Charlie

 

[Eklipze3k]

Even mine with a leak isn't that low, and I can smell petrol every time I go anywhere near mine (hence why I'm not driving it right now until I get a chance to sort it out!).

 

[blu73]

Fraz, you can SEE the petrol coming out of yours, nevermind smelling it.

 

[cheiron]

17mpg ...problem resolved!!!

By the way thanks Blue73 fuel line joints were my original thought too as that was what I had just disturbed, did re-did them twice -no joy!

So ..started going through everything to do with the fuel system bit by bit, trying to work it out. Sorted out connections to the air pressure reg on the air filter inlet and so on all seemed to be working. Tried disconnecting and re-connecting most items but seemed to make no difference. (Engine switched off in between connecting of course!) Until I disconnected the air tubing from the manifold to that separate square electronic sensor thing next to the ECU. Noticed a hole in the underside of the tube hidden from view where it was clearly sucking in air. Did not think this would make much difference but repaired it anyway and Wow!! Suddenly engine runs perfectly no more hunting and black haze from exhaust and so on. +Fuel gauge no longer dropping like the stock market after the latest Euro news!!

Simple as that!! Great little car by the way -mechanically seems as tough as old boots!!

 

[blu73]

that is the map sensor well done

 

[cheiron]

Since replacing the fuel temp warning light sensor -temp light on console has glowed in relation to the temp. I,e the hotter it gets -the brighter. -This seems useful as a sort of rudimentary temp gauge, -has never done this before so I assume it is a later mod?

 

[chrisb7777]

There were two sensors, one for the gauge and one for the light so you must have the gauge version hooked up

 

[cheiron]

Thanks Chris B that would explain it ..did some versions of Ciecento have a temp gauge? No provision on mine, -have moaned about that in past as by time light comes on often you are getting steam as well ! Remember this from days when the cooling fan seized (loose armature magnets).

 

[Eklipze3k]

The Cinq's had a gauge, the Sei only ever had the 'oh crap' light. I believe there is a gauge +ancillaries for sale in the classifieds unless RuSZ has already sold it?

 

[RuSZ]

Nope, still got it and still for sale Iif anyone wants it;

https://www.fiatforum.com/classifieds/showproduct.php?product=26998&cat=500

 

[blu73]

thought it was only the cinq sportings & sx's that have temp gauge.. the s model didn't have a gauge i don't think.. Been a while since i been in a s though.

 

[Eklipze3k]

Of course, you're right, I forgot about that

 

[blu73]

so yeah if you don't have one, try find a set of clocks out of a sporting.