Yep its the injectors ticking if it stops at 3.2k rpm.
The 307 injectors aren't coded to the ECU, but you do need to check the part numbers, 306s are 044, the less ticky ones are 062 and 076 iirc.
The 307 injectors aren't coded to the ECU, but you do need to check the part numbers, 306s are 044, the less ticky ones are 062 and 076 iirc.