the aux coolant pump is an electric after run pump. continues to run coolant through the engine after you turn the ignition off. wouldn't be causing an overheating problem. a lot of times leaks can be traced to the aux pump. if you have coolant leaking near the middle of the back of the engine that is the culprit.

 

Depending on how long you ran the car hot can vary what's wrong. Are you burning coolant? Pull your spark plugs out and look at them, hopefully they're not steamed cleaned lol. You would also have white smoke emitting from your exhaust. You could have a cracked block/head, bad head gasket, or a broken hose. Wont know until you pressurize the system and look. Thermostat stuck closed could also be a culprit. Also you could pull the hose of the expansion tank and check to see if the water pump is creating flow, if not then you have a bad water pump. Good luck.

 

i got out my inspection camera and i could see evidence of the aux pump leaking so i ordered a new one. But you guys don't think that will make any difference in cooling the car while its running? i noticed when i changed the thermostat that it used regular green coolant instead of the pink stuff. could that have anything to do with it? radiator hoses top and bottom are just about the same temperature so i dont think its a clogged radiator. water pump supposedly only has 1k miles on it and when i pulled it off the other day for the thermostat none of the fins were damaged and it seemed to be spinning fine. it gets hot doing basically any driving that isn't downhill lol. also doesn't cool effectively when i'm stopped. all the fans seem to be working

how do i pressurize the system to test it? i know that when its hot and i open the coolant reservoir it will bubble up through the opening like its pressurized. yeah i lost some coolant when it overheated. it'll start leaking coolant from the bottom of the reservoir if it gets up the 2/3 heat.

its running a little rough so the mechanic told me to put in a new fuel filter and spark plugs. also ordered a set of TT diverter valves since both of mine were shot.

 

okay so i was flushing the coolant system at my parent's house (my dad has a 6 car garage with an oil pit so its awfully convenient) and since i was able to get underneath the car, i let it run to flush out the heater core and noticed water leaking right under the flywheel. so i got the inspection camera out again and the aux pump was leaking pretty badly. so i think thats a big part of the problem right there. it was hard to tell if i was leaking coolant cuz everytime it got hot it would boil some coolant out. but at least i know now.

also, another question, while i was under there, i noticed that right before the driver side cat, theres a hose clamp thats loosely slipped around the pipe. is there supposed to be a hose clamp on the exhaust side of the turbo? i wouldnt imagine there being any rubber hosing on the exhaust side....

 

Replaced diverted valves, aux pump, fuel filter, flushed cooling system and filled with g12 and replaced spark plugs. Runs way better and more power but there still must be a boost leak somewhere. It's also still running a little hot after I've been pushing it or driving uphill, I think I might have aNother leak somewhere or having the green coolant in it might have damaged the water pump. Ill probably do all the timing components and water pump next. How do I test the fans to make sure they're working correctly? They all turn on but can they turn on and be overpowered or something?