Would a faulty coolant temp sensor cause my CRX Si to have a hard time with cold starting? I have heard people claim this and i am confused as to why that may be. I was thinking that the reason to my starting issue would be more likely due to an old/faulty fpr (i say this b/c i have replaced the fuel pump and strainer, filter, and have replaced fuel injector gaskets). Why would someone assume a faulty coolant temp sensor rather than fuel delivery components? If the sensor were broken would the gauge on the cluster stop working? etc. Any help will be appreciated. Thx

 

I don't think it would have anything to do with the CTS. How's your battery that can make it have hard starts in the cold, also the cold can make it turn over slowly depending on the compression in the cylinders. The cold period just makes cars work like ****.

 

absolutely, the CTS changes resistance depending on temperature of coolant, sending information back to the ECU giving it the information needed for the engine to run properly.

 

Most of the time when a coolant temp sensor fails it runs rich. Which in turn can foul the o2 sensor and runs rough till the vehicle warms up.

 

I know the cts can make it run rough, it just doesn't seem very likely that it would be the cause of a hard start. I could be wrong though, whatever, good luck either way.

 

https://honda-tech.com/forums/honda-crx-ef-civic-1988-1991-3/faulty-coolant-temp-sensor%3D-hard-starting-2485847/

 

the CTS IS the cause of a rough start until warm up, i had this problem, take care of it and get it fixed.