"Redwood" > wrote in message
...
> 1993 Audi 80 2.0 single point (ABT engine).
>
> It's my dad's car, had it from new & been well serviced over the years.
> I'm trying to diagnose poor top end performance and thinking it may be the
> lambda sensor, or any other suggestions welcome.
>
> Starts & drives well but gutless at top end. Up to about half throttle it
> has plenty of pull but put your foot down for overtake or approaching
> inclines and there isn't much there and takes a long time to build up
> speed - usually have to knock it down the gears. Feels as though it wants
> to go but a lack of fuelling at top end is holding it back. In fact if
> your cruising along say at half throttle and plant your foot down it feels
> like it actually slows down before very slowly starts to build up speed.
> TPS & various other sensors appear ok (within Autodata spec) & checked for
> any vacuum, air leaks. The injector unit to manifold rubber flange looked
> a bit worn & cracked but I've replaced that.
>
> Only thing I can think of is the lambda sensor as the cars done about 120k
> miles on the original so was wondering if that could be on its way out and
> slow at sending the correct signal to increase fuelling at top end?

Well it did turn out to be the lambda probe. Went for MoT yesterday and it
failed on high emissions (0.5). The lambda passed but garage man said it was
sluggish. New probe fitted and emissions passed & the car is running loads
better with now plenty of pull at top end. Previously if you tried to hold
the revs at a fast idle it would pulsate down & up slightly but now it holds
steady.