Running water sound. 99 Blazer

I have a running water sound coming from the vents on the dash during acceleration. Any ideas?

The gurgling noise if from air being in your heater core. Normal, and can be fixed if you follow my advice.

When the engine has sat overnight and is cool, open the rad cap and check to see if it is right up to the neck for us.

but ONLY when the engine is bone cold.

Let us know.

I did it, it is low.

How much did it take to fill it up to the neck?

Remember to only use dexcool and no other coolant.

I prefer the premix Prestone Dexcool for topping up seeing it is ready to go.

You will also have to get another rad cap at your local parts store for your specific vehicle. We run a 15-16psi system and you will require a cap for our vehicle that allows that.

What you are seeing is the rad cap not sealing and sucking in air when the coolant is retracting when it should be drawing coolant from resovoir to keep it topped up.

Top up the rad, install the new proper cap and drive and then go check the next day when it is cold again.

It should be up to the neck and perfect.

Then pour some coolant into the overflow tank so that the coolant level is at hot even when the truck is stone cold.

Engineers say to keep the system overflow tank a little higher for a healthy cooling system.

Good luck.

Note that many of these engines are leaking coolant into the crankcase, manifold gaskets leaking. This will ruin the engine if allowed to continue. Fill the radiator and top off the coolant tank to the "hot" mark and keep a close watch on the level. Change the oil if even close to being due.

Note that many of these engines are leaking coolant into the crankcase, manifold gaskets leaking. This will ruin the engine if allowed to continue. Fill the radiator and top off the coolant tank to the "hot" mark and keep a close watch on the level. Change the oil if even close to being due.

Coolant in the oil is something that cannot be missed seeing it will turn the oil into a chocolate milk when you look at it. It cannot be mistaken and is easily seen.

This person needs a new rad cap. Even when you top off the tank, the rad will not draw coolant from it seeing it is drawing air through a defective seal.

This is what happened to me.

I had the same problem with my blazer. I lost heat, and found the dex crap sludged up. I ran a Prestone cooling system flush through the engine for 4 hours. Then flushed with plain water until clear. I drained the block. Then refilled with plain old ethylene glycol anti-freeze. I haven't had a problem since.

True, but in this case, he has noted a low amount of coolany in the rad.

FrankJC,

What gives? Did it fix it?

I have a running water sound coming from the vents on the dash during acceleration. Any ideas?


You also want to check and see if your Dexcool is still orange in color. If you take off your radiator cap and see brown sludge in there your Dexcool has morphed into mud. Take it to a radiator place and have them do a complete flush of your system or you will have problems later on.