Car stalls no reason????

[project240coupe93]

ok, so i have a 1993 240 coupe. just put a 1996 s14 ka in there (110k) saw donor vehicle. changed the injectors/fuel rail to s13 dohc along with s13 ecu and harness just so its easy. now onto the bad part she runs fine i set the idle to about 750. but when im dirving down the road if i push in the clutch n hit the brakes to stop itll just die. its not a big problem but i dont have any clue as to why its doing it. sometimes when i just idle itll die to. also when it dies about 50% of the time the winshield wiper will wipe once..... ya kinda crazy but im desperate for some info...so let me know what you think.By the way Hi Nico! first post lol.