space-junk

iTrader: (1)

alright guys, i got an odd situation here that im hoping you can help me with...

im gonna start out by saying that i know i have a leak somewhere either in my throttle body or in the intake manifold somewhere, i just cant for the life of me find it, and frankly, with no job, i cant afford parts right now...

the weird thing is, my truck only leaks when its raining... it sounds stupid, but im serious... whenever it rains, i know i have to have a jug of water on me to fill up the overflow... it'll overheat most when going highway speeds when the water pump is spinning fastest... that in of itself confuses me the most... it wont overheat when its 90+ outside, but when its 30- it does...

now, i know that its not getting into the oil because i check constantly... but the only thing that i can think of is the atmospheric pressure playing a role... when the atmospheric pressure is high, its more than the internal pressure of the motor thus keeping the coolant from leaking... then when the AP is lowest like when its raining, its lower than what the motor produces...

if any of y'all brainiacs got an idea, please do help me... id really hate to overheat and blow a freaking head gasket when its pouring rain...

sb5walker

I assume its coolant you're leaking? 'Cause you don't actually say.

If coolant, run a cooling system pressure test and pull the air hose off the throttle body to see if it's leaking through the cold idle up valve (IAC/AAV).

You might have more than one issue - if overheating with the heater on, you may have the problem described in this article by 4Crawler:
http://www.4crawler.com/4x4/CheapTri...tml#Thermostat

space-junk

iTrader: (1)

yes, its leaking coolant...

and seeing as tho i have the V6, its not that particular problem... i just replaced radiator, hoses, thermostat and all coolant less than 6K miles ago, and water pump was replaced back in 07...

EDIT: when the rad was replaced, i did a full cooling system flush, including the heater core, and also burped the truck correctly... this problem just cropped up in the past 800 miles and only with cold weather...

DupermanDave

I would have done the flush before you put a new radiadtor in. That way all the junk cleaned out of the old system doesn't contaminate the new radiator.

Tubbyfatty

When the motor is cold, squeeze the upper rad hose and listen for bubbles. thats how I found a few of my leaks. I just fixed several leaks on my truck. Water neck on top of the intake plenum was leaking, heater hose at the back, throttal body lines were leaking.

I had no idea where it was leaking from but when I squeezed the upper rad hose, I could hear bubbles then I just looked around.