I took the lambda sensor off last night whilst the car was running, tried it cold and when the engine had warmed and it made no odds at all. Thinking my problem is down to that. Would anyone agree?
 
any luck sorting your car out?
when Lamba sensors go bad it causes the engine not to idle smoothly and rev up and down use more fuel than normal. Engine will do this running hot or cold as the ecu is getting the wrong readings from the Lamba sensor
The engine will not run good if you disconnect it. more likely you need to change the temperature coolant sensor and clean the throttle body with carb cleaner also take the spark plugs out clean them with a wire brush as they could be sooted up if engine is running rich.
 
Is it the tall block or short block 1.6 75hp engine? The small block 1.6s are not the best, the newer ones have iffy oil pumps. If it is the small block trying to fit the AFT engine becomes a bit more complicated. In either case though replacement engine would be cheaper than a rebuild.
 
any luck sorting your car out?
when Lamba sensors go bad it causes the engine not to idle smoothly and rev up and down use more fuel than normal. Engine will do this running hot or cold as the ecu is getting the wrong readings from the Lamba sensor
The engine will not run good if you disconnect it. more likely you need to change the temperature coolant sensor and clean the throttle body with carb cleaner also take the spark plugs out clean them with a wire brush as they could be sooted up if engine is running rich.

No lambda sensor drew no results. Coolant temp sensor you say? The temp gauge does move it just takes forever to get hot and as soon as heaters are put on the temp drops real quick.
 
Is it the tall block or short block 1.6 75hp engine? The small block 1.6s are not the best, the newer ones have iffy oil pumps. If it is the small block trying to fit the AFT engine becomes a bit more complicated. In either case though replacement engine would be cheaper than a rebuild.

How would I tell? Probably a daft question I know...
 
The small block leans towards the front of the engine bay and the tall block leans towards the back. :)

It leans towards the front. Lambda sensor was a waste of £50. I had problems with it overheating not to long back. Changed the water pump and thermostat and it stopped overheating. Think that'll have fried a sensor?
 
Sorted at last!

I was getting really chuffed off. 15-20 mpg and 10 minutes a day to warm the car before driving. Expensive, lengthy and just a pain in the neck all round!

Anyway one coolant temp sensor later courtesy of GSF for 8 quid or so and all sorted. Just done a 400 mile round trip to Birmingham and averaged 55mpg. On a 10 year old car that was full of crap I'm happy with that.

So thanks for the advice guys. Had a problem sourcing the part but you lot really helped.