Water temperature sensor??

Hello guys! I’m actually from the Mercedes forum, but 2 years ago I actually bought a 323er as a winter car. Since he liked me so much, I had him set up and she drives him now. Now he’s been ticking around for 3, 4 weeks! First I thought it was a detonator, and I changed distributor cap & fingers, ignition cables & candles, unfortunately without success It’s now even so annoying as if you were riding a wild bull! So now I know myself at the starship, but have little idea of Mazda. I have of course read through the forum and have come across some threads that describe this problem quite well. I’ve read that it’s either the dealer for the water temp., the ignition coil or ignition distributor can be. Is it true that? Where can I find the water temperature sensor & how do I check it? What do you think it might be? Now she wanted to drive the long weekend to Croatia! What do you think / can stay with the car so far?