5S-FE MK2 Non-Turbo Engine Fluctuating Idle... Water Temperature Sensor? [Archive] - Toyota MR2 Message Board

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1991 MR2 Automatic Surging / fluctuating idle while stopped and while driving. I found that when it surges the Idle Speed Control valve is opening, so when I cover that vent I have no issues. I tested the Water Temperature Sensor and it was giving me erroneous readings at times and sometimes gave me the correct readings. I sanded the contacts for corrosion and it seemed to work fine for a while. Now the problem is back again, I plan on replacing the sensor but I can