Hey guys in was looking to see if anyone could answer a quick question about my recently rebuilt s4 n/a engine running too cold while driving. I noticed that during regular "running temperature" my temp gauge seems to be reading just about the C line and doesn't really rise any higher unless I smash it and even at that still it rises very slowly.So my questions are: is it bad to be running that cold? Do I just try another thermostat?
Here's a picture of my running temp...

 

Check the coolant temp sensor, it might not be the t-stat if you're engine has warmed up already. Do your fans turn on correctly? If so, check the temp sensor.

 

Pretty normal for an S4. That's about where normal operating temp is on the gauge. The confusion you are experiencing caused them to switch to a different gauge in the S5. Unfortunately making the S5 gauge much less useful.

 

I have a stock clutch fan that stays on while im driving. Is there any cons to having a cold temperature while driving..?

Also if I am running a stock exhaust (with smog pump) set up for a 87 n/a and a hks intake... is the smog pump needed? its only hooked up to the hks filter, cause when i punch the gas the intake almost sounds like a duck call. want to just take the belt off. Will I have any problems not running the pump?

 

My temp gauge reads the same and once in a while my coolant indicator lights up then turns off.