Hello everyone,
Today while on the way back from lunch I hear the chime, see the red temp light, and the coolant temp boxes maxed out. Car went into limp mode, was able to get it off of the highway and into a parking lot. Ran for maybe a minute after being alerted. I opened the hood and noticed that the coolant expansion tank hose was dripping, coolant levels were a bit lower than the minimum line, another concerning thing was the bubbling coming into the tank from the line that was leaking. Once I got the accessport plugged it was reading temp of 245.
I let the car sit for about 10 minutes and decided to see if I could get the temp to come down with the help of max defrost/heat. This worked and the temp slowly got itself back down to 190’s. I cleared the codes (overheat, limp mode, and something about the cylinder head temp) so that I could get out of limp mode. The weird part about it was even though it was on defrost with max heat the air was still coming out ice cold. It wasn’t until driving 10 minutes that the heat came on full blast. The car would also bounce between 180 and 190 and when I got up to highway speed the temp would skyrocket again to 210. The car drives fine, no smoke, no smell out of the exhaust, idles fine. Oil looks like fine, coolant looked fine, tiniest bit of air coming out of the tank when I put my hand over it while running but I feel like that’s normal as the coolant circulates?
Is that coolant tank likely the cause of the overheating because it was low and maybe developed an air bubble or should I be concerned for the headgasket?
About the car:
MY16, mountune rad, last fluid change summer of 20 with 70/30 motorcraft coolant/distilled water. Full bolt on, E30 tune. No recent mods done other than replacing my old coilovers.
Where it was leaking until it got below that level:
Today while on the way back from lunch I hear the chime, see the red temp light, and the coolant temp boxes maxed out. Car went into limp mode, was able to get it off of the highway and into a parking lot. Ran for maybe a minute after being alerted. I opened the hood and noticed that the coolant expansion tank hose was dripping, coolant levels were a bit lower than the minimum line, another concerning thing was the bubbling coming into the tank from the line that was leaking. Once I got the accessport plugged it was reading temp of 245.
I let the car sit for about 10 minutes and decided to see if I could get the temp to come down with the help of max defrost/heat. This worked and the temp slowly got itself back down to 190’s. I cleared the codes (overheat, limp mode, and something about the cylinder head temp) so that I could get out of limp mode. The weird part about it was even though it was on defrost with max heat the air was still coming out ice cold. It wasn’t until driving 10 minutes that the heat came on full blast. The car would also bounce between 180 and 190 and when I got up to highway speed the temp would skyrocket again to 210. The car drives fine, no smoke, no smell out of the exhaust, idles fine. Oil looks like fine, coolant looked fine, tiniest bit of air coming out of the tank when I put my hand over it while running but I feel like that’s normal as the coolant circulates?
Is that coolant tank likely the cause of the overheating because it was low and maybe developed an air bubble or should I be concerned for the headgasket?
About the car:
MY16, mountune rad, last fluid change summer of 20 with 70/30 motorcraft coolant/distilled water. Full bolt on, E30 tune. No recent mods done other than replacing my old coilovers.
Where it was leaking until it got below that level:
