205 1.6 Gti Splutters At 4000 Revs Issues

[scon1 0]

looking at buying a project car thats had engine swapped but it splutters at 4000 revs, clears both sides of this tho and runs great its a 1.6gti engine thanks in advance ( ive not got it yet but looking for idears before i buy thanks harry

[Anthony 1,003]

Probably the ignition amplifier is failing (or has been replaced and no/insufficient heat transfer paste applied).