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My 94 civic EX with the D16z6 Vtec has been running at about 210 degrees, which I know is too hot. I recently had to replace the thermostat but that didn't make a difference. When cold my idle surges up and down occasionally as well. I also had a small leak in my radiator recently that I put stop leak in to fix temporarily. I'm getting it checked today to see if it's my map sensor, and might just put a new radiator in it. I know it needs a coolant flush as well, it's pretty slimy in there. What else could be causing these issues? Or am I right on track to fix it? Thanks.