Leaderboard

AFAIK, that year still used the open loop/closed loop tuning in the ECU. Which means it's running off 'set values' 'til it warms up, then starts reading the sensors - such as O2. I don't want to be the one that suggests an O2 sensor - and it not fix the issue. If you do, it should be OEM or Denso quality. Also, the CTS/temp sensor can cause issues like you described. Ideally you'd have an OBD2 reader/scanner - even the low-end $ ones can read 'live data' for O2 voltage and CTS temps.