97 Ranger 2.3L Misfire when cold

[Dogface]

The problem I`m having is, the thing starts up right away idles perfectly, then I start down the road go 1000ft or 1500ft to a stop and it starts to miss and shake and has no power. It will do this untill it is at full operating temp then it runs fine and idles like a singer sewing machine. I have ohmed out the temp sensor and the values change as the temp changes, other things have been replaced just not the temp sensor.

Can the temp sensor be faulty midway and will that make it misfire and send
a code? I have not had a Temp sensor code yet just the misfire. I plan to replace the sensor but thought I would see if anyone has had this problem before, Any ideas!

Thanks

 

[Autto27]

the ECT? engine coolant tempurature sensor? no that wouldnt cause a rough idle. it only measures the tempuature of the coolant and sends information back to the pcm which in turn adjust your long and short term fuel trim to match the engine tempuature for best running conditions. my guess would be wires or dis packs. run your engine at about two grand and lightly mist water over the wires, if you see little sparks mid air it means the wires are bad, this can be caused from buying cheep wires or not changing wires. it could also be plugs, check your ignition system, 90% of the time misfires are and ignition issue.

 

[Autto27]

your EGR may be sticking when the engine is cold, then as it warms up it will float freely, that would explain the feeling of a miss and a rough idle, you dont want the EGR opperating at idle. it screws with the Stoichiometric Ratio