2005 Sunfire coolant problem

[mva]

I am helping a friend out tomorrow with her 2005 Sunfire. She has a slight smell of coolant inside the car that gets worse when the car is hot. I do lots of work on cars but I am not familiar with the Sunfire/Cavalier.

I had a first look and I didn't see any evidence of a heater core leak - carpet is dry, windows are clear, coolant level is good.

I could not see any obvious leaks but I could smell coolant under the hood near the reservoir. I am thinking it could be the vent/cap on the pressurized reservoir or a slight head gasket leak or ?

Other Questions:

How does the coolant reservoir cap work? I tried turning but it would not open.

I was thinking of changing the coolant (it is original) and adding Bar's leak or Prestone stop leak. What coolant? Does Bar's leak work well?

 

[cronk]

Ecotech or the pushrod 2.2?

I know the older cavs/sunfires with the pushrod 2.2 had a coolant cross over tube on the front of the motor that would rust through and leak.
I think an 05 would be Ecotech, those are not known for head gasket issues, although possible.
I would be checking hoses, clamps and pressure caps first.
Do you have access to a pressure tester?
Thats your best bet.

 

[cronk]

Another thought, check the water pump for leaks.

 

[daves87rs]

If you can smell it, it's a hose.

 

[Chris142]

Cracked Radiator tank? Could be coming from a lot of places.

 

[mva]

Ok I had a good look at the car this morning.

It is a 2.2 Ecotech and there are no obvious signs of coolant leaking anywhere. There is a very slight residue on the bottom of the water pump. I sure hope it is not the water pump - it looks like a big job to change.

The pressure test idea is good but I don't have a tester. I am going to check out renting or buying one.

If I don't find the leak I will going to try changing out the dexcool and adding some sort of stop leak additive.

Here is a good link in case others have to change the water pump:

http://ww2.justanswer.com/uploads/jettadan1/2010-10-23_221258_water_pump.pdf

 

[cronk]

If its a water pump, stop leak products won't help a bit.
They can fill small holes but cant fix a seal leak on a water pump.

 

[rpn453]

Originally Posted By: mva
It is a 2.2 Ecotech and there are no obvious signs of coolant leaking anywhere. There is a very slight residue on the bottom of the water pump. I sure hope it is not the water pump - it looks like a big job to change.


Is the weep hole wet? If so, it's going to need a water pump soon. No additive can improve that.

 

[kelpie]

I suspect it's your radiator cap (not really a rad cap, but the cap on the tank). I've had 2 go bad on my son's car and the first one was hard to remove and I smelled antifreeze inside the car.

 

[mva]

Originally Posted By: kelpie
I suspect it's your radiator cap (not really a rad cap, but the cap on the tank). I've had 2 go bad on my son's car and the first one was hard to remove and I smelled antifreeze inside the car.


I think you are probably right. I didn't like the feel of the rad cap coming off or going back on.

There was no coolant coming from the water pump weep hole and I could not find a leak anywhere.

I ended up changing the coolant with prestone dexcool and I added a bottle of prestone stop leak.

For others changing coolant on this engine, in addition to the rad drain, there is a drain bolt on the bottom of the water pump. This bolt drains about 1/3 of the total coolant out of the block and water pump.