I noticed yesterday while changing my distrubutor O-Ring that my temperature sensor pigtail wires were hanging on by strands and down my harness (previous owners ) had spliced in the pigtail horribly ,
Basically Can This Be The Cause Of My Hard Strart Roughnand High Idle 1200-1500 rpm ? My car takes long too start and when it finally starts it idles high and once warm it start with no problem ??? Need help guys

 

I don't know what kind of engine or car but if it's the temp sensor that the ecu reads then yes it can cause an issue. High idle probably not but hard to start and rough idle I would say yes. The ecu will not know the engine temperature. The temperature offsets will be incorrect and cause too much or too little fuel to spray.

 

Because the ECT sensor supplies the ECU/ECM with engine temp. if it is not working, depending on what is wrong, the symptoms are easy starting when cold but hard starting when warm, [running rich] and poor gas milage or hard starting when cold but easy starting when warm, [running lean].

A/F ratio needs to be rich when starting a cold engine but leaned out once warm, the ECU/ECM does this with info from the ECT sensor if the sensor is bad and always indicating a cold engine it results in easy cold starts and hard warm starts, the rverse is so if ECT sensor always indicates a warm engine.

A number of other facters are involved, but basic symptoms like the above point to a bad ECT sensor.

Either way, bad wiring needs to be repaird properly. 94

 

Thanks Guys for the help , after this snow clears I'll replace the pig tail and buy a new sensor , hoping this is my issue

 

I'm having the same exact problem as you. Mine starts up idles at 1500rpm. But nothing else. Check the wires to see if it's getting enough power. If the plugs don't get anything close to 5 volt then your problem is in the plug or wires. And if the sensor don't get 200-400 ohms after car is warm then change the sensor. I can't figure mine out since the only problem I have is high idle and no vtec. I got power in the wires. Sensor is at 300 something ohms. Drives perfectly except the idle. **** sucks. Maybe yours could be fixed easier if you haven't tried the above.
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Found my issue the ECT was fine , but the actual harness was rigged up wires cut up so I spent two hours heat shrinking and soldering took out the sensor cleaned it and it worked perfectly starts just fine , but for idle I'm guessing my FITV needs to be cleaned and adjusted bc idle is still high 1500 rpms !

 

Friend had same problem with his car he changed the iacv and it was good try cleaning yours .