Technical Bravo 1.4 12v - exhaust manifold vs MPG

[aurick86]

Engine 1.4 12v a.k.a. "gas guzzling pig"
The other day i was out fiddling, and payed a bit more attention to the exhaust manifold, specially to where the lambda probe goes in to it.

Might the positioning of the lambda probe be a cause for the 1.4's thirst for petrol?
I mean it isn't in the direct path of the gas coming from the exhaust,
i think that in time the amount of suth and ash collecting there might some what influence the mpg.

do you think that if the lambda probe would be in the direct gas stream that would make the car run to lean?! i mean how can this car run lean?, even if it got double the MPG it still wouldn't be running lean.

Just a thought; there must be a way to make this engine more economical.

 

[mikeyprg]

i think your on to somthing i havn't seen the engine bay of the 1.4 but isit space cramped? maybe blocking off that one with a screw-bung and relocating it to one of the downpipes . It does seem a daft place to put it as its not getting a good reading.

 

[aurick86]

i think your on to something i haven't seen the engine bay of the 1.4 but isit space cramped?

moving it down the pipe would mean that there would be less heat on the sensor (bad thing), but then again it is out of the heat at the moment so that wouldn't be to bad.

engine bay has a lot of space- small engine.

the engine is almost ok when running at higher speeds.
also there isn't a big mpg drop when running it pretty revved-up.
So thinking the air flow over the lamda probe might be a factor.

 

[aurick86]

Where and how is the lambda probe on other fiat models?
maybe on the more economical models.

 

[jimmyybob]

The oxygen sensor on some is way down the front pipe under the gear lever area and on the punto its mid way down the front pipe a foot away from the manifold.