I've got a pretty steady leak coming from the lower right side tank on the radiator as you are facing the front. I haven't completely investigated it yet, but I'm assuming I'm better off just replacing it now. Is this a hard "driveway, weekend job"? I'd love to do this myself this weekend.

If you have proper tools you should be able to replace it this weekend.

Replace it FAST, not a hard job, might be a couple hours of tinkering, I blew an engine because I thought I could limp one along.

Got it in this afternoon. Thanks to the Bengals crappy performace, I got an early start. Took a few hours but was a piece of cake. Thanks.

In need of help again!!! I thought I had this done, but evidently not.

I took the van to work today....after a few minutes the temp gauge shot up near the redline, then back down. I assumed I probably just had some air in the system. I took it home from lunch and opened the cap and the 2 bleed screws and ran it for a few minutes, then tightened back down. Temp gauge seems ok now (at least so far) but the low coolant light stays on... I've filled it back up a couple of times and can't see that it's loosing coolant anywhere. I poped the hood and get a strong "burning" smell... not really antifreeze, more like the engine is HOT smell. What have I missed???

I turned the a/c on and the fans came on, but I can't get them to come on while idling. Is that normal, I don't recall.

Please help, this is driving me up a wall.

My first thought a week or so ago before I noticed coolant was streaming out the right side tank was that I'd blown the intake gasket again. I've had that replaced 3 times in 10 years. The last time being not quite 2 years ago. Head gasket was the next thought, but oil seems to be ok.... not white at all and was actually a tad low (so I don't think I'm getting coolant in my crankcase, but not 100% certain).

Go to Advanced Auto or Auto Zone get a loaner pressure tester pump up the system to around 12 psi use a flashlight and look for any signs of leakage.
Look at all hose connections,water pump weep hole, leaking hose fitting.
If you don't find any thing leave the system pressurized and run the engine.
If the gauge pulsates a head gasket is a probable cause.

when you say pulsate, do you literally mean up down, up down? it's definately fluctuating a bit, but I wouldn't say it pulsates. Thanks for the ideas.

When is the last time you flushed the system? WP been changed?

Whats the exhaust look like? Excessive white smoke? Sweet Smell?

water pump was replaced about 4-5 years ago... system was flushed about a year ago.

Not noticing any white smoke... nothing crusty on the oil fill cap, nor is the oil milky.

when you say pulsate, do you literally mean up down, up down? it's definately fluctuating a bit, but I wouldn't say it pulsates. Thanks for the ideas.
Normally if a cylinder is leaking it will move up and down when it gets to a leaking cylinder.
If you have another vehicle without problems pressure this vehicle and compare to the problem vehicle.
Look at water pump weep hole for heavy stains as they can be fine leak and stop before they let go completely.

Well...good news. The pressure check didn't reveal any issues. I bled the system again and it seems to be ok now. I think I still just had some air in the system. The low coolant light hasn't come on in over a day now, temp gauge has been steady and well on the low side and radiator is still full.

Thanks all for the quick responses and help!!!

RT

I hope your problem was just air bubbles. I know the system is a pain in the ____ to bleed. In the spring I had our local Chevy dealer replace the coolant and even they didn't get all the air bubbles out the first time, had to bring it back to them to re-bleed the system. All was well after the second try.

Intake gasket leaks can come and go also, keep tabs on it....... Good Luck :-)

Still not right...

Had a shop do a leakdown test. They found it to be ok - - no intake or head gasket leak. They said the coolant level sensor was probably bad.

I haven't replaced the sensor yet, but something is not right. Level sensor still goes on and off while driving... but every now and then the temp gauge will shoot up to red, then come right back down to normal. It's done this twice now. I thought there was air in the system but not so sure now. It otherwise runs on the cool side.

I went out to check the coolant level tonight and there was some back pressure in the system....coolant flowed out of the open neck and went everywhere. It had been parked for a couple of hours after a short drive home. What else could be happening? Anything else to check, this can't be right? At my whits end with this thing.

Still not right...

Had a shop do a leakdown test. They found it to be ok - - no intake or head gasket leak. They said the coolant level sensor was probably bad.

I haven't replaced the sensor yet, but something is not right. Level sensor still goes on and off while driving... but every now and then the temp gauge will shoot up to red, then come right back down to normal. It's done this twice now. I thought there was air in the system but not so sure now. It otherwise runs on the cool side.

I went out to check the coolant level tonight and there was some back pressure in the system....coolant flowed out of the open neck and went everywhere. It had been parked for a couple of hours after a short drive home. What else could be happening? Anything else to check, this can't be right? At my whits end with this thing.
You can try a new pressure cap for the bottle. Watch the level in the bottle only replace the sensor if leaking or it says low on radiator fluid with a full bottle.
http://www.tooltopia.com/ Search LIS75500

you mean the overflow? yes, it stays full, actually a little over full.

Get one of those radiator caps with the pressure release lever. I use a 12psi rather than the 16 the factory installed. When you come home pop the hood and lift the release valve up. This will force coolant (and any air) out into the overflow tank. Do this several times to make sure you have all the pressure equalized, then close the valve back.
As the engine cools, it will suck coolant (and no air) back into the system via the valve in the radiator cap. By releasing the built up system pressure after you park the car, you increase the amount of coolant that will flow back into the system as it cools. Doing this two or three days in a row will purge any air left in the system. This is because the coolant that flows out into the tank may contain air, but the coolant that is sucked back when its cools contains no air. You might even hear the bubbles escape in the tank as you relieve the pressure. If the overflow tank every becomes empty, you have introduced air into the system again and must start over.

The pressure sensor itself can fail with a leak. Look on the left side of the radiator (passenger side) just above the lower radiator hose that goes to the pump. The sensor is located just above the hose. Look for weeping signs on top the hose or behind the sensor. You should smell the sweet odor of antifreeze if you have even a small leak.

If there is no smell, I'd start to suspect a manifold gasket may be starting to go again.

I will try that. Thanks

Well, I continued having issues with the temp going to red and the low coolant light coming on. They finally found the leak...it's the head gasket.

$1475 if the heads are ok and not warped, $1950 if they need some machine work. Ouch.

How many miles? If over 100k, I'd seriously consider rebuilt engine! The engines go for around 2k and come with 100k 3yr warranty. Don't throw good money after that engine when its worn down anyway.

Just out of curiosity did any of the shops, or you, ever put a block tester on the coolant system? A block tester is different than a coolant leakdown tester. It specifically tests for combustion gasses in the coolant system.

Yes. I believe that is exactly how they finally discovered the leak.

I've had horrible gas mileage for quite a while now... something like 10/city, 14 hwy. Used to get about 19/26. Guess I know why now.

I know I'm throwing money at a worn engine (110K), but hopefully it works out. I need another 3 years or so out of the van, then I can run it into the lake. :)

[QUOTE=rodgerturner;
I know I'm throwing money at a worn engine (110K), but hopefully it works out. I need another 3 years or so out of the van, then I can run it into the lake. :)[/QUOTE]

You can use the same money as what the heads will cost you and put it towards a brand new rebuild. I wish I'd done that instead of heads the 1st time. I ended up doing the heads, then only 2 years later (and months of frustration) the same thing happened. I got the engine--with a warranty of 100k/3yr and my wife has been able to take the van anywhere without fear of breakdown.

In a couple weeks we're taking it on a road trip of 1400 miles--with no worries. In my experience, if the manifold gaskets go bad before 100k and then it happens again within a couple years, the engine is just too damaged. Get another. I've had three of these vans and fixed all three. The absolute best performer has been the rebuilt engine. You can chalk that up to maybe I don't do a very good job replacing the head gaskets (one of the vans I put new heads into), or maybe I was just unlucky, but read these forums (venture/olds/pontiac) and notice how many folks wind up with the same problems over and over. Unless your installer offers you a warranty on the head gasket, you will worry every time the smallest thing goes wrong.
Get an engine--with a warranty--enjoy your van.

You can use the same money as what the heads will cost you and put it towards a brand new rebuild. I wish I'd done that instead of heads the 1st time. I ended up doing the heads, then only 2 years later (and months of frustration) the same thing happened. I got the engine--with a warranty of 100k/3yr and my wife has been able to take the van anywhere without fear of breakdown.

In a couple weeks we're taking it on a road trip of 1400 miles--with no worries. In my experience, if the manifold gaskets go bad before 100k and then it happens again within a couple years, the engine is just too damaged. Get another. I've had three of these vans and fixed all three. The absolute best performer has been the rebuilt engine. You can chalk that up to maybe I don't do a very good job replacing the head gaskets (one of the vans I put new heads into), or maybe I was just unlucky, but read these forums (venture/olds/pontiac) and notice how many folks wind up with the same problems over and over. Unless your installer offers you a warranty on the head gasket, you will worry every time the smallest thing goes wrong.
Get an engine--with a warranty--enjoy your van.
A quality rebuilt is the way to go don't waste your money. I was a a scrap yard and a man was on his third engine from the yard. All of this when I told him where to get a long block for only $60.00 more than the scrap yard engine he was upset.
The yard gave the replacement engines but no labor.