White smoke coming from the exhaust

2003 VOLVO XC90
103,000 MILES • 2.9L • 6 CYL • 4WD • MANUAL
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STEVIED1512
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  • 1 POST
Intermittently, when idle the car will start to smoke and then as soon as you pull away and start driving, it stops. Moreover, when at cruising speed it can sometimes feel a bit ‘lumpy’.
Nov 6, 2019 at 12:40 PM
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SCGRANTURISMO
  • ASE Certified Mechanic
  • 4,897 POSTS
  • ASE Certified Mechanic
Hello,

White smoke from the exhaust is usually a sign of burning coolant in the combustion chambers of the engine. This usually happens from a blown head gasket, cracked cylinder head, or cracked engine block. Sometimes, depending on your vehicle, a coolant crossover tube in the intake manifold will leak coolant into the intake and it will be introduced into the combustion chambers that way. A little bit of steam is normal for a modern vehicle to make when it is running properly from the catalytic conversion of hydrocarbons to water and less harmful waste products. he exhaust heats up and turns the water to steam, which looks like white smoke. If you are burning coolant, there will be a noticeable loss in coolant and the smoke will have a sweet smell to it. Here is a link down below explaining everything in more detail:

https://www.2carpros.com/articles/white-smoke-or-steam-coming-from-the-exhaust-pipe

Please go through this guide and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros
Nov 6, 2019 at 3:46 PM
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JIS001
  • ASE Certified Mechanic
  • 3,412 POSTS
  • ASE Certified Mechanic
I just wanted to jump in as well. Was that video taken early in the morning? When the catalytic converter does it's job it is normal to see steam coming out the exhaust. The catalyst is turning the byproduct into water. All vehicles will produce steam during warm up. If you have more information let us know please but steam out the exhaust is normal.
Nov 7, 2019 at 11:17 PM
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