b93hatch18

i have been chasing down problems for awile now i have a b18b1 in a 93 hatch converted to obd1 i have had a rough cold idle and running problem scince i got the car. cleaned the iacv and noticed the fitv was blocked of took it apart cleaned it and hooked it up those took care of my hunting idle and my cold idle of like 750 still runs rough when its cold and sometimes when the temp falls into the negatives its a no start. i retimed the car cuz i knew it was 2 deg advanced just kindof trying things out and i set it back to stock. so now to the intake air temp, pulled the codes its throwing a 10 (iat sensor) noticed that the wires wer rubbed thu on the connector they were in good shape just bare in a little spot on each sealed those back up tested the reasistnce on the sensor and it read 1.4 ohms at like 40 deg which is in spec. disconnected my bat to clear the code and 10 came up again. today i noticed when i was letting my car warm and holding it at a stedy 2000 rpm to speed it up a little the temp gauge didnt rise very sslowly and the instant it started to rise my car started running better. sooo where to next haha, thermostat? coolant temp sensor? what else can throw that code