I am new to the PFC and the whole tuning thing in general. I have searched but have yet to find my particular issue. The highest water temp reading my PFC has displayed while driving is about 59 degrees. This was on Georgia Summer day, with a high in the mid 90's. Yeterday, the display sat at around 17 degrees and topped out at 23 degrees, after sitting in traffic.

Question is, would these low temps indicate a bad sensor, or an incorrect PFC setting? And if the problem is the sensor, and not the PFC, could this be the cause of any drivability issues due to an overly rich mixture or something?

Thanks in advance for any insight.

 

Sounds like your sensor is bad or your water isn't topped up. Yes, your car would be running rich at all times.

thewird

 

Thanks for the response. Well, I changed the sensor yesterday and I'm getting the exact same results. The engine was recently rebuilt, and I have been reading of cases where the plugs for the fuel thermosensor and water thermosensor where switched. But I'm wondering, if this were my case, would the indicated water temp still fluctuate the way it does? Mine will skyrocket when I shut the car down after a run, then come back down once the car is started...?

 

Sounds like they are switched to me, unless the thermostat is stuck. The fuel temps will skyrocket when the engine is shut down. That's how old engines would vapor lock. It's normal.

 

Probably is switched, forgot people do that lol. Simple test would be to disconnect the coolant temp sensor. If there is still a coolant temp number in the pfc, they are obviously switched.

thewird

 

Thanks for the help guys. Turns out they were switched, just as you suspected. I sweitched them back, and everything is good. Runs MUCH better now lol! Anyway, thanks again.

Phil