Overheating/Hissing from under intake.

[vortex2450]

Unfortunately here I am once again coming to you guys with another issue.

After a 15 miles drive I noticed that I was running hot (Needle on "N" ) about the time I arrived at my destination. I popped the hood and there is a hissing yet gurgling noise coming from under the intake. Not near the throttle body, it sounds like it's coming from the valley under the fuel rails. There's no steam but a slight tinge of hot coolant when I sniff the area.

The car has ran fine for the past couples day since I had the water pump off, the heat blasts red hot and the overflow res hasn't dropped much at all. I drove it experimentally for about 2 miles and it will hover at operating temp then slowly work it's way towards N. The temp didn't go over N but I also parked before I would give it that chance.

My first thought was a coolant line to the TB or the IAB coolant block but the sounds is without a doubt originating from smack dab under the middle of the intake. I'm slightly baffled because I don't know exactly what's down there but before I make the drive back home (I'm still at a friend's house) I was hoping someone could throw some ideas at me...

I'm so tired of this love/hate relationship I have with my car... I hasn't gone more than week since the swap without throwing stupid stuff like this at me.

-josh

 

[StAnGbAnGeR]

I'm having a similar issue with my car, especially since the weather in Chicago area has been hot the last few days. Minus the hissing, my temp gauge rides N then comes back down. I've been told to replace my t- stat, have you tried this?

 

[Bob Gervais]

Coolant crossover tube leaking?

 

[jayro]

Coolant crossover tube leaking?

That's the right area that is being described. Is it possible that the o ring on the back of the water pump isn't seated completely? I had a hissing sound on mine when I still had some air in the system. Have you tried getting it to operating temp and then burping it by squeezing the upper radiator hose with the cap off? Just be careful when you open the radiator cap. Cover it with a thick towel or a number of shop rags since it will be under pressure.

 

[vortex2450]

Coolant crossover tube leaking?

BINGO!! That was it, the o-ring on the water pump side of the tube was *****. I took t apart on the water block side and ending up breaking the stud for the thermostat housing, that cost me about an hour...

It's looking good now. Thanks!

I'm having a similar issue with my car, especially since the weather in Chicago area has been hot the last few days. Minus the hissing, my temp gauge rides N then comes back down. I've been told to replace my t- stat, have you tried this?

That has been the norm for me, does it usually get up high during traffic or just randomly during highway speeds? If it's the latter, case is probably air in your system, other than that, the needle just goes back down once your going faster and the water pump is pumping the coolant faster.

That's the right area that is being described. Is it possible that the o ring on the back of the water pump isn't seated completely? I had a hissing sound on mine when I still had some air in the system. Have you tried getting it to operating temp and then burping it by squeezing the upper radiator hose with the cap off? Just be careful when you open the radiator cap. Cover it with a thick towel or a number of shop rags since it will be under pressure.

I'm not a fan of letting the car get up to operating temp before taking the cap off, I've found it's infinitely more effective to just leave the cap off and use the upper hose to burp any bubbles out as the cars running and warming up, just my alternative to not getting coolant everywhere

-Josh

 

[frosho]

Yeah... definitely don't open the radiator cap on a hot engine, whether it's running or not. That is a terrible idea.