Water temp sense dilemma

[Raptoreborn]

Hello Dsmr's

I was in the process of my winter bolt-on build up on my 2g. When I noticed the water temp sensor wire connector not fully on. It was very noticeable the water temp sensor had two prongs. Okay,so I hit up the closes mitsu parts dealer for the correct 3 prong temp sensor. Whats funny is I did a motor swap about a year ago but never noticed this stupid mistake. Also the reason for the upgrades are the whole stuttering BS. still a issue!
My plans are to beef up the fuel system, injectors, fuel pump, fpr, and for good measure a fmic.
I guess my questions are:

1. Would this cause the radi fans not to kick on? Thank god for a/c button!
2. " "for fuel starvation at high rpms (3500 & up)?
3. " "to over heat?

 

[cbrue122]

1. Yes, I had a bad coolant temp sensor and the radiator fans would not kick on automatically when needed.

2. I am not sure about the fuel starvation, but that sounds more like the fuel system is inadequate for the amount of air you are flowing.

3. Overheating is more than likely a result of the radiator fans not kicking on automatically.

Another point about that coolant temp sensor is if the ECU does not have any input from that sensor it will see a default value of something like -40F and keep the engine in the cool up mode to prevent any damage. This would result in your car running really rich all of the time. Was your gas mileage pretty crappy? The super rich operation may be a cause of your stuttering as well.

 

[Raptoreborn]

1. Yes, I had a bad coolant temp sensor and the radiator fans would not kick on automatically when needed.

2. I am not sure about the fuel starvation, but that sounds more like the fuel system is inadequate for the amount of air you are flowing.

3. Overheating is more than likely a result of the radiator fans not kicking on automatically.

Another point about that coolant temp sensor is if the ECU does not have any input from that sensor it will see a default value of something like -40F and keep the engine in the cool up mode to prevent any damage. This would result in your car running really rich all of the time. Was your gas mileage pretty crappy? The super rich operation may be a cause of your stuttering as well.

-Thanks for the feedback-
cbrue122

Yes your right, my car does run real rich and gets around 14-15mpg. Should be upwards of 20mpg or more. I tried leaning it out with the afc and it
somewhat cured the stutter at high rpms.

This is the reason that I started to experience cold start issues about a month ago.

 

[cbrue122]

-Thanks for the feedback-
cbrue122

Yes your right, my car does run real rich and gets around 14-15mpg. Should be upwards of 20mpg or more. I tried leaning it out with the afc and it
somewhat cured the stutter at high rpms.

This is the reason that I started to experience cold start issues about a month ago.

You are welcome. Glad I could help.

Yeah, that mileage is nothing to write home about; 30mpg is not out of sight for a properly running engine.

If by chance you are replacing that coolant sensor make sure it is the Mitsu OEM unit and not a generic one from the local Auto parts store. I replaced my bad sensor with a generic unit and the cold starts were still a problem.

Assuming you have been running quite rich for such a long time you might want to think about replacing the front O2 sensor. They get contaminated much quicker in such a fuel rich environment and closed loop fuel control suffers as a result. Just a suggestion; not completely necessary.