Coolant keeps blowing out the coolant reservoir CAP

kinkyllama · Post by **kinkyllama** » Wed Apr 23, 2008 3:36 pm

Is this a feature of some sort? cause the cap is on there really good...and no worst than it ever has been.

A few days before it started happening the hose to my thermostat popped off and I lost the clip so I epoxy the hell out of it to keep it together until I got a new clip. I think this is unrelated though as the coolant boiled out of the cap 5x last night. Running it hard didn’t seam to make much of a difference. One time the car was cold and I drove about five miles when it started. I filled it back up and the car was cool when I drove as hard as I could for about 10 miles and it didn’t do it. The threads on my coolant reservoir could probably be in better shape but the cap screws down very very tight.

My friend has this happen to his car and found the lower hose to the radiator was too old and collapsed from the pressure of the water pump causing it to block off the flow.

Thanks!,
Danny

exist3nce · Post by **exist3nce** » Wed Apr 23, 2008 11:48 pm

Yes that is a safety feature of sorts. The cap will start to release pressure if it builds too high. I think it has the pressure rating right on the cap. I don't know if your car is actually overheating or something is wrong with the cap. The coolant will start to spray out of there if it gets too hot and starts to boil. I've had this happen a couple times when doing consecutive high boost highway pulls. I just filled it back up and everything seemed ok.

kinkyllama · Post by **kinkyllama** » Thu Apr 24, 2008 8:21 am

exist3nce wrote:Yes that is a safety feature of sorts. The cap will start to release pressure if it builds too high. I think it has the pressure rating right on the cap. I don't know if your car is actually overheating or something is wrong with the cap. The coolant will start to spray out of there if it gets too hot and starts to boil. I've had this happen a couple times when doing consecutive high boost highway pulls. I just filled it back up and everything seemed ok.

The car didn't over heat any of the times it did that...it never over heated untill the other day but it still didn't blow out the cap.

Ugh.

kinkyllama · Post by **kinkyllama** » Wed Apr 30, 2008 7:57 pm

Last time I was having overheating problems because the fans weren't turning on I replaced this piece:

Not that sensor with the wire, but the one next to it with the red ring. After that the fans started working again. WTF is that thing? When I took it out I don't remember there being any water on the other side and there are no wires going to it so I don't understand how it would effect anything.

I'm going to just fix my dents, replace my engine harness....then look into the problem. I can drive around if I'm carefull and I'm going to prom for the first time soon and would rather drive my nice car than the busted crap expedition. Btw, yes, I've been out of high school for awhile but graduated early and never got to go to prom.

Pir0 · Post by **Pir0** » Wed Apr 30, 2008 10:43 pm

Does a spade go on the end of that? If it does it looks like the teperature sensor for the dash, which funilly enough controls the fan switch

exist3nce · Post by **exist3nce** » Wed Apr 30, 2008 11:04 pm

I have no idea what that red thing is. I know the piece beside it is the coolant temp sensor which sends the temp to the ECU directly. From what I've observed, the ECU then sends that information to the dash gauge and also will trigger the relay for the fans when the temp gets high enough.

kinkyllama · Post by **kinkyllama** » Thu May 01, 2008 12:06 am

Pir0 wrote:Does a spade go on the end of that? If it does it looks like the teperature sensor for the dash, which funilly enough controls the fan switch

A spade? Nothing goes on the end of it...that's why I don't understand what the hell it does.

exist3nce wrote:I have no idea what that red thing is. I know the piece beside it is the coolant temp sensor which sends the temp to the ECU directly. From what I've observed, the ECU then sends that information to the dash gauge and also will trigger the relay for the fans when the temp gets high enough.

Yeah that's my understanding too. If I were to unplug it will it go into like some sort of safe mode to where it'll turn on the fans?

BosnianLanos · Post by **BosnianLanos** » Thu May 01, 2008 8:33 pm

It looks like a spade should go at the end. I had one of those too in my Lanos, and there WAS an electrical connector at the end. It slips off now and again, and the fans kick on and my temp gauge drops to zero.

Maybe the electrical system was different in the Forenza and the fans get signal over the CTS...

Maybe?

Triple check around the site to see if there are any loose wires.

daewoomofo · Post by **daewoomofo** » Thu May 01, 2008 9:21 pm

yeah that looks just like the think i couldnt find, it was my cts. its a horrable desigh on the connector used to make contact.

kinkyllama · Post by **kinkyllama** » Thu May 01, 2008 9:48 pm

BosnianLanos wrote:It looks like a spade should go at the end. I had one of those too in my Lanos, and there WAS an electrical connector at the end. It slips off now and again, and the fans kick on and my temp gauge drops to zero.

Maybe the electrical system was different in the Forenza and the fans get signal over the CTS...

Maybe?

Triple check around the site to see if there are any loose wires.

It's never had anything plugged into it. Before when my fans weren't coming on a replaced it and it never had anything connected to it...then the fans worked with the new one.

MMamdouh · Post by **MMamdouh** » Fri May 02, 2008 1:17 am

strange... on my 1.5 SOHC that red thingy is the temp sending unit for my temp gauge on the cluster... only difference is that my sensor is located on the coolant passage of the intake mani.

if it is the same on your car then their sould be a wire going on top of that sensor... is your temp gauge working fine? if it is then you are getting signal for your gauge elswere and we are left with the same question... what the hell is this??

what was the P/N of that part? what was written on the package??

MMamdouh

hap_suu · Post by **hap_suu** » Wed May 06, 2009 8:36 am

Overheating may not be the reason why coolant is blowing. The reservoir cap is there to keep the pressure on but it will not stop anything that it is already boiling. In other words, if there is a small leakage started anywhere that prevents coolant system to build pressure, the coolant will start to boil early. Pressure cooker works the same way. You put pressure so the water heats above 100 C without boiling and your food cooks better and faster.

MMamdouh · Post by **MMamdouh** » Thu May 07, 2009 2:44 pm

then this is clear evidence that the valve on the cap is faulty... can you get us a pic for the cap??

MMamdouh

The original daewootech forum

Coolant keeps blowing out the coolant reservoir CAP

Coolant keeps blowing out the coolant reservoir CAP

Re: Coolant keeps blowing out the coolant reservoir CAP

Re: Coolant keeps blowing out the coolant reservoir CAP