Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Coolant smell but no sign of leak


Whenever i drive for a while and get out of the car, i smell burnt coolant. I couldn’t locate any leaks and the dealer didn’t either. They have advised to change the coolant reservoir cap. Well, that did not help and i continue to top the coolant once in a while.

I would appreciate any hints.

That happened to me a couple of years ago, shortly after I replaced the upper radiator hose. I knew that a very small amount of coolant was escaping, based on the odor in the garage when I parked the car, coupled with almost no reduction in the level of coolant in the radiator.

As it turned out, I just needed to “tweak” one of the hose clamps in order to eliminate the seepage. I would suggest that you check all of the hose clamps, including the ones on the heater hoses.

Model-Year, Please. About How Many Miles On The CTS ?

No doubt coolant is leaking onto hot engine parts and steaming away instead of dripping. A gasket leak could be the culprit. More information requested from you could help.


Addition: In addition to VDC Driver’s good suggestion that hoses / clamps are possibly suspect, I see that certain 04-05 CTSs have faulty radiators that often appear to have leakage near the lower hose. However, a very small leak when the car is hot may not result in drips or puddles. A revised radiator is available through GM. When I get the Model-Year I can dig deeper into defects.

I had similar experiences on a few of my cars.

88 Chevrolet Beretta - There was a small coolant bypass hose under the manifold. The clamps needed to be tightened occasionally.

2000 Blazer - Leaking intake manifold gasket, needed to add a pint of coolant after a month. Two years ago the radiator developed a crack in the side tank near the top. Couldn’t find the leak until the top of the fan shroud was removed.

Has the dealer done a dye test to pinpoint the source of the leak. The dealer should be able to diagnose an intake or head gasket leak. Perhaps a second opinion is in order, especially if the CTS is still under warranty.

Ed B.

often you can spot a seep like this by the accumulation of discolored dry coolant at the leak point. Or, you can look at the coolant connections with the engine hot and running, preferabley by revving it in neutral.