89 TR surges on light acceleration

Problem has been there, but in the past it was rare, and only when engine was still cold. On light acceleration in second gear it would set up a lurching or surge, but downshift would eliminate it.
Now it's more frequent and in the higher gears as well, even when warmed up. Once the revs are high enough it lightens up but I can still feel it.
Any suggestions as to where to look?
Thanks.

 

what you understand under: on light acceleration?

 

I would define it as "moderate" acceleration. As soon as it starts the surge I down shift to eliminate it and accelerate harder.
It seems to be RPM related as it clears up with higher RPMs.
Thanks

 

I have discussed this same problem with a well known Ferrari fuel injection expert in the UK.
Apparently it was caused by the engine being slightly too weak. A slight recalibration of the fuel distributer fixes the problem and he has had many systems sent back to him for the fix.


P

 

what light you mean???
sorry, but don´t understand what you mean

 

now I understand:
light here means not sun"light", it means small, or not heavy
sorry please for missunderstanding

 

No problem. You understand English much better than I understand German.
Thanks for trying to help.