[urq] cold starting problem

[SpotatAshleys]

I still have a cold starting problem on my 87 WR.
I always try to start it as per the manual.e. with slight depression of pedal as engine is cranked. Works fine when warm or after left for several days but hardly ever fires first time just left over night. If it does not catch first time I have to put foot flat to floor and crank for 6 or 7 seconds. It always fires eventually but starter never sounds like it is spinning fast enough.
I have changed the starter (new)  - no difference.
Changed battery (new) - no difference.
Checked fuel pressures - fine
Changed injectors & seals (new) - no difference
New leads, rotor & cap - no difference.
Cold start injector tested and works as it should.
No apparent air leaks

Any suggestions?

I have been through the audi fans archive and running short of ideas now - intend to change fuel pump check valve, filter and accumulator next but any suugestions would be gratefully received.

Many thanks

Keith

'87 WR