2001 Chevy Impala Coolant Leak

Hi Hank:
Most likely the coolant is leaking from the t-stat housing and making its way back. It could be something as easy as the hose itself. Give those a check. Also, take a flashlight and check around the intake gasket areas. You may have an intake gasket leaking. Look for coolant or evidence of a coolant leak.

Let me know what you find.

Joe

Thanks Joe, I recently replaced the thermostat thinking that was the casue of overheating. I was careful to ensure that there was no leaking when I did it. I can see behind the thermostat housing black residue and coolant pooled below that on the engine and frame. There is white smoke coming from the exhaust, it is light and earlier I attributed it to cool weather, but today is mild and I still see it.

Hank:
White exhaust usually indicates an intake leak or head gasket. Somehow coolant is getting into the combustion chamber. Check the oil for coolant contamination and the coolant for oil. If there is no evidence of contamination, you will need to have a compression test done. Also, based on where you described the coolant to be, it sounds like an intake problem. Does the car have a 3.1L V6? It's a common problem with them.

Let me know what you find or if you have other questions.

Joe

Joe,

My Impala is the 3.4L v6. Here is the scenario from today. Started the car to move it around back to work on. Large ammount of white smoke from teh exhaust which subsided to a small steady flow. The car runs fine, without teh thermostat showing it overheating. When the low coolant light comes on I shut it off. I can see steam coming from the engine under and behind the thermostat, I can see where the coolant is running toward the rear of teh engine comaprtment and pooling onto the ground. I still cannot pinpoint source of the leak. There is a block Oily buildup on the side of the engiune in this area. I am geting some engine cleaner so see if that helps me locate the source. The Oil seems fine and I dont see a "mikshake" residue. I am pretty certain that it is origionating from the area behind the t-housing.

Thanks,
Hank

Hank:
Let me know what you find after you clean off the engine. I hate to say it but my gut feeling is the intake gasket. If you have a lot of white smoke, that usally indicates coolant geting burned in the combustion chamber.

Let me know what you find.

Joe

Joe,

I found the leak I think it'e the upper intake manifold (following the seam, it runs below the t-housing) the leak appears to be at the point the seam angles upwards towards the rear spark plug housing. There still isn't waht I'd call alot of whie smoke. but its present and the pooling under the car from the leak is obviouse. If I am follwoing you this is the upper intake gasket.

I have a Haynes Manual, is there a better guide to preforming this repair? My car differs in the upper intake manifold has six fasternes (there is one or two for brackets I think), not the 12 shown. I'm guessing this is a variation in model years.

Thanks,
Hank

Based on your description. it sounds like the intake. Not being there limits me. Regardless. if it's leaking, it needs repaired.

As far as your manual, yes they provide variations for different years. Mitchell and Chilton are other manuals you could check out. They are both a quality resource. I was able to up load a picture of the upper intake. Let me know if this is what you see.
[
img]https://www.2carpros.com/forum/automotive_pictures/249084_Upper_Intake__34_GM_2.jpg[/img]

Joe

Joe,

That looks like it. It seems like the hard part is remembering where everything goes that you have to disconnect to get to it. I guess that is what digital cameras are for.

Any tips besides patience before I tackle this one?

Thanks for all your help with this, I truly appreciate it.

Hank

Patiences is about all I can tell you. Good luck and if you run into trouble, let me know and we'll figure it out.

Joe
PS: Let me know how it goes, and use some masking tape and a sharpie to mark items to help remember locationa.

Joe,

I truly appreciate you help with this. I'm going to give it a go Saturday morning. I'll keep you updated.

Thanks,
Hank

Joe,

I'm down to removing the lower intake manifold. I have removed 8 bolts and given it a few dozen good raps all around (hammer and wood block). The Haynes manual referrs to a casting boss (below the coolant temp. sensor) as a pry sopt. All other parts have come off with little problesm. This still seems pretty secure in place. Should it take alot of effort to remove the lower intake manifold, or am i missing something ?

Thanks,
Hank

Hank:
I looked it up and all I see are the 8 bolts. It may require more persuasion with a rubber mallot. The gasket may be stuck.

Sorry it took so long to get back. I lost a parent on Friday and ended up in the hospt myself last night.

Joe

Joe,

Please no apologies are necessary, you have my heartfelt condolances. I hope you trip to the hospital in nothing too serious.

I finally did get it off, just being overly cautious since this is my first attempt at an auto repair of this scale. I'm geting ready to do the cleanup of the parts. The inside of the valve covers and the lower intake maniforld have a brownish goo coating it. Do I clean this off?

Thanks again,
Hank

Thanks, Hank. Everything will get back to normal I guess. Regardless, yes, clean everything as best as you can. I always use parts cleaner, but if I don't have it, brake cleaner works great. Also, make sure that everything is clean of old gasket material, and dry. Also, when you tighten evrything, follow the torque sequence in your Haynes manual.

If you run into any trouble, let me know. Also, make sure to run a straight edge over parts to make sure there is no warping.

Joe

Joe,

I'll get the parts cleaned this week and start reassembly over the weekend. Good tip on using the straight edge to check for warping-I most likely would have skipped this if you hadn't mentioned it. I'll update you as things progress.

Thanks,
Hank

Hank:

It seems like you have more than enough ability. Just take your time and use common sense. You'll be fine.

Joe
Have a great holiday season.

Hi Joe,

Sorry for the 4 month absence-personal problems, winter weather and job layoff have all taken up my time. Nice day today so I went to finish up and encountered a new problem. The rear right corner of the upper intake maniforl and 1/2 of the threaded section for the lower intake manifold broke. Very odd since I wasn't applyi9ng much pressure to it and I am positive I didnt drop or strike it. I can see the gasket in the exposed corner so I know its a deal breaker. Can this be repaired or does tio have to be replaced?

Thanks,
Hank

Hank:

Welcome back. As far as the intake, it will need replaced. I would try to find a good one from a salvage yard or you might be able to find one aftermarket.

As far as it breaking, it was most likely already cracked.

Joe

Thanks joe. I asked around this afternoon and found a reputable salvage yard with good prices. I'll get over there this week and see what they have.

Hank