car cuts out when engine temp is half way when stopped

hi i have a 1991 vw jetta gx petrol manual and i had it kept in a makeshift drive way 2 slabs and i went to take it out and had to put a lot of power on to the clutch and it started smokking real bad so my dad poured water in to a hole where all the smoke was coming out from and now when stopped in a line of trafic when the temp is at half it will stall the batrey light and the oil light flashes and they are both ok took it to a garage and they ajusted throtel cable and temp dosent rise as quick now not stalled yet but not been in heavy trafic do you think this could be the problem or maybe something else the engine was idelling to slow the mechanic said

It does sound like the idle was too low, but I hope they didn't raise it by pulling the throttle cable tight. I don't know if you UK car is carbureted or fuel injected. It would depend on which it is to say how to properly adjust.

they puled the throtel cable and put in a washer then the clip to save it going back to original position i think it is carburated