1.1 Fuel Economy Problems

[minimaniacwhyard 17]

have a little minor issue. my car is using astronomical amounts of fuel for a little 1.1. had the sparks out and it looked like it was running lean.

a little bit more information. if driving within the lower rev range she hesitates a little bit. like a little misfire. if i pull the choke out a little it sorts out that. meaning in my opinion its running lean for definite . but the using loads of fuel. a full tank in 270 miles.

i can understand that its on a carb and therefore uses more fuel than injection but this seems excessive. i cant see any leaks anywhere either.

 

any suggestions would be appreciated. as im stumped. also not sure how to set these carbs up. only ever been involved in su carbs

 

[TooMany2cvs 65]

Sounds like there might be an air leak - is the carb bolted tightly to the manifold? Try spraying some carb cleaner around the base of the carb with the engine idling - if it speeds up, then there's probably an air leak.

 

There's not much to set up on a single-choke Solex.

[minimaniacwhyard 17]

Should have said i checked everything was tight. Couple of loose buts like the bit where the choke attaches but i couldnt find any air leaks and i soaked it in carb cleaner

[TooMany2cvs 65]

Thought about this dim-and-distant thread this morning. Our 1.1 has been feeling a bit lean of late, a little hesitant, and not quite right. But, after giving it a few new bits on Sunday, it's transformed. Much smoother, nicer from cold, starts easier. Oh, and the last tankful's seen 46.5mpg... OK, all motorway, but quite a chunk of that at <ahem> tappet-rattling rev cruise altitude in top (4th)...

 

Oil & filter (5w30 full synth - probably a bit thin, but it seems happy, no oil pressure light even at hot idle)

Plugs, HT leads, dist cap, rotor arm, air filter.

Check tappets.

 

Not exactly low mileage, either - 148k miles...