07 Matrix runs poor when cold

[JPNNH]

My Matrix with 5 speed seems to miss & then starts surging when cold...after it warms up it runs fine. Anyone else have this problem & if so how did you fix it...Thanks in advance.

[tundrat3]

mine too!!! at first it was doing it while it had rained or was raining which led me to believe it was wires/ distributor/electrical due to condensation. but now that the cold weather is on its way it is doing it then as well. im not happy bout this. frig its only september......round here winter brings in temps of -30, -40 oC. i will be taken the car into the dealer in a couple weeks....will post what they have to say.

[v6er]

its possible your ECT sensor is failing in the hot position. Therefore the computer never knows when the engine is cold (when its cold it adds fuel because the fuel does not vaporize as well) you would have to check the resistance of this sensor. If this is the case it well have very low resistance.