Coolant leak only when engine is running?

2001 PONTIAC GRAND PRIX
126,000 MILES • 3.8L • V6 • 2WD • AUTOMATIC
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ROERIGRAIDER1
  • MEMBER
  • 2 POSTS
Slow coolant leak passenger side under car. Only when running. Could it be the heater hose plastic elbows I read about? No sign of any oil in coolant or white smoke??
Feb 24, 2021 at 8:48 AM
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JACOBANDNICKOLAS
  • Experienced Mechanic
  • 110,240 POSTS
Hi,

It is very possible that it could be a heater hose. However, remember coolant will travel and may end up somewhere different than where it starts.

Here is what I suggest: We need to determine the source before a repair can be made. So, here is a link that explains how to pressure test a cooling system. You can do this when the engine is cold to locate the problem. Also, you will need a pressure tester. Most parts stores will lend one to you free of charge.

https://www.2carpros.com/articles/radiator-pressure-test

Here is a link that explains in general how to repair a leak:

https://www.2carpros.com/articles/car-is-leaking-coolant

_____________________________

I hope this helps you locate the problem. Once you confirm the problem, let me know what it is and I can further direct you.

Take care and God Bless,

Joe
Feb 24, 2021 at 1:01 PM
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ROERIGRAIDER1
  • MEMBER
  • 2 POSTS
Thanks.
Feb 25, 2021 at 2:49 AM
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JACOBANDNICKOLAS
  • Experienced Mechanic
  • 110,240 POSTS
You are very welcome. Let me know if you need help or have other questions.

Take care,
Joe
Feb 25, 2021 at 9:58 AM
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