Idling speed, excessive fuel consumption

[Efe]

> Hi All,
> 
> It had been a long time (about 1.5 years) since I got back to the
> underhood of my Audi 90 Quattro (1990) NG Type engine with Jetronic fuel
> system. As now I have decided not to sell it once more and refurbish it
> one more time.
> 
> My current engine problems are quite obvious:
> 
> 1. High fuel consumption (have to rev-up more to gain power and speed)
> 2. Low idling speed (even when the engine is heated)
> 3. Loss of engine power (It used to even go up the steepest hills on the
> 4th gear as now its nearly dropped down to 2)
> 
> So, where could be the problems ? As I am guessing, it may be the lambda
> sensor, CO mixture unit etc... But havent got the slightest idea yet :)
> 
> Best wishes,
> 
> Efe
> 
> P.S. : Lately I got hold of few CD's from www.autocd.com (as low as 10$)
> which gives me all the parts info on various WV and Audi models. Diagrams
> etc. Superb. Does anyone have a copy of the factory repair manual ?