2008 MS3 running hot

crooked deal

Greenie N00B Member
Hey everyone,

Just joined the forum today, I was somewhat active on the old forum back in the day.
I have a 2008 MS3, about 90K miles, owned the car for 10 years. Just did a bunch of work, cleaned the intake valves, installed thermal gaskets on TB and intake, while it was apart I also did an EGR delete and TB coolant bypass.
I have now noticed the car is running much hotter than it has in the past. Before I would see ECTs no higher that 200 with the AC running in summer temps. Now the car is running between 210 and 215, with the heat running full blast, without heat it will get hotter, but the dash gauge still is not showing a high temp, it's still below halfway.
I have burped the cooling system twice just in case I introduced an air bubble when doing the TB coolant bypass, but no change. Both large radiator hoses are eventually getting hot, so I guess the thermostat is opening, but maybe not fully? The car has not went past 225 deg.
I'm stumped, obviously this happening after all of the work I did makes me think it might be related.
Any advice would be greatly appreciated, and hello to everyone on the forum!
 
Heat running full blast, with the a/c button pressed, should be keeping it below the max temp (215).
 
It's normal.
This

Do these cars tend to run a little hotter without the EGR system functioning? Thanks for the info!
It's probably more that bypassing the TB coolant has reduced the surface area for the coolant to go through, and with the cold air coming I to the TB there has to be some cooling of the Coolant and warming of the intake air, wait that's the reason you bypass the TB cooling.
Speeds run hot, fans only kick on at what 220-225? IIRC
 
So the reason for the throttle body coolant bypass is to reduce the intake air temperature? And there is minimal side effect from doing this? So then I’m assuming the coolant goes through the throttle body just as another source of coolant cooling?
 
So the reason for the throttle body coolant bypass is to reduce the intake air temperature? And there is minimal side effect from doing this? So then I’m assuming the coolant goes through the throttle body just as another source of coolant cooling?
Coolant runs through the throttle body to keep it from freezing in the areas it gets stupid cold.
 
Any further tips on maximizing cooling on the stock radiator? I ordered a Koyo radiator but due to covid it'll be months before arriving, and I've got some time on track coming up. Just run the heat on full blast? And should I stick with fl22 or is there anything better?
 
Any further tips on maximizing cooling on the stock radiator? I ordered a Koyo radiator but due to covid it'll be months before arriving, and I've got some time on track coming up. Just run the heat on full blast? And should I stick with fl22 or is there anything better?
What are your temp issues?
 
What are your temp issues?
None so far, just want to be prepared for track use. I've only done one HPDE, but really didn't consider the risk of overheating and didn't monitor coolant temps.


I've ordered a Koyo radiator and jbr oil cooler, but they won't arrive before an upcoming weekend at mid-ohio.
 
When the thermostats on this car fail they generally fail open so you will have issues getting to temp and run too cold. When you did the bypass did you just loop the lines together? Is the rad fan still running ?
 
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