For the past 6 months or so (since owning), my GXL has always taken quite a while to warm up. This held true on days that were well over 95 degrees. I had always attributed this to the fact that I have a massive Koyo and 2800CFM shrouded e-fan(which the previous owner wired to run constantly).

Two days ago I discovered that my thermostat housing gasket was leaking coolant and not knowing the last time the system was flushed; I took the liberty of flushing the system and replacing the gasket. I have noticed since then that the vehicle reaches normal operating temperature much quicker now ( I.E. four minutes from a cold start on a ~50* morning).

This seems rather mysterious to me. The system was bled properly and the fan still works. I would also like to add that upon reaching operating temp, it does not rise any higher.

I am not so sure if this is a problem or not, but it seemed a little odd. Insight?

 

radiator size doesnt lower temps. that is the job of the thermostat. the radiator thickness plays a role when it comes to the rate at which the water cools. the bigger it is, the faster it cools. contaminants in the coolant or a bad water/coolant ratio will play a part in this as well. most likely, the thermostat was stuck.

PS. NEVER TRUST THE STOCK GAUGE. get an after market unit.

 

Thanks for the reply. I apologize for the way I had written that statement. I did not mean to infer that the radiator played a role in warmup temp. Also, I am definitely aware of the stock temp gauge being pretty useless. So far, it has been at least varying.

The weird part about it is that the car would warm up previously. It just took a lot longer than now. Maybe it is like you mentioned and there was just a bad ratio.

 

did you change the thermostat? on an S4 the stock temp gauge is fine, it just doesn't have numbers.

 

It is an S4. I did not replace the thermostat as I tested it in hot water and it worked fine.