Skip the auto shop - Our mechanics make house calls

Q: white smoke after head gasket repair

asked by on

I had a blown head gasket repaired. I am no longer losing coolant. I changed the oil and filter twice to make sure all coolant and oil mixture is out of the engine. However, I still see intermittent white smoke from exhaust. I know this is coolant still burning. Is this normal and how long will it take to get all coolant out of the engine? Is there anything I can do to speed up the removal of remaining coolant from engine?

My car has 121000 miles.
My car has an automatic transmission.

A: When ever an engine blows a head gasket and...

When ever an engine blows a head gasket and leaks coolant into one or more cylinders and pushes the coolant into the exhaust flooding the catalyst and muffler with coolant. After the repairs to the engine are made to fix the leaking head gaskets the engine can then be started. Once started the exhaust heat will now start to burn off the coolant and water that was pushed into the exhaust system. When this fluid is heated it will come out the exhaust as white smoke or steam. It may take a few days to a week to burn off all this fluid out of the exhaust. One of the quickest ways to burn off all the coolant quicker is to hold the throttle at about 2000 rpms when in park for about 10 to 15 minutes. This will get the exhaust to its hottest level and burn off excessive fluids out of the exhaust. Just a note that the coolant that got into the exhaust system may of contaminated the O2 sensors and the substrate of the catalyst. If you start having check engine codes for the O2 sensors or catalyst efficiency then you may need to test and replace the catalyst and O2 sensors to repair the codes.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: High idle in the morning and after sitting for 5+ hours

Hi, thanks for writing in. I'd like to start by saying, you haven't wasted your money. Even if your issue hasn't been repaired, they did some quality maintenance that will help your truck last many more miles. I understand your...

Q: where is the location of crank position sensor in 2001 s600

Hello, thank you for writing in. The crankshaft position sensor is located on the back of the engine towards the top of the transmission bell housing. It will be towards the driver's side, and be tucked in close to the...

Q: How do I fix load muffler noise from my Lexus RX 300

You will need to have the exhaust inspected to see where the exhaust is leaking. Sometimes the flex pipe connected to the engine goes bad and leaks. Other times the muffle can rust through causing this. Have a muffler shop...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.