By January 16, 20080 Comments Read More →

Does White Smoke Out My Tailpipe Mean a Blown Head Gasket?

Think you might have a head gasket problem? Watch this short video.

Reader Question Austin I found my problem and looked over the answers you gave and your article on the different smoke types that come from your exhaust pipe. My problem is the white smoke.

I am looking to buy a 1994 Roadtrek 190 Popular with an Automatic 318 V Dodge engine. It is a van conversion type of motor home. I had the owner take it into a mechanic and met him there. I asked the mechanic to do a compression check along with a total mechanical check up of the van. The service manager said that they didn’t do compression checks but listened to the vehicle. The van was in the shop for 45 minutes.

The vehicle has been sitting for several months, but I drove it two weeks ago and it handles well, no stuttering or pausing and idled well. The mechanic gave it a good bill of health even though is has 148,650 miles on it.

He said that there was a slight leak in the differential, some bulbs were out on the outside and the windshield wipers were hard. The owner has done or had the transmission rebuilt, replaced the fuel pump and filter, resealed the gas tank, resealed the wheel bearings, serviced the generator, put in all new hoses and serpentine belt and had some kind of AC replacement part replaced.

The owner drove it for 17 miles to the mechanic in about 30-35 degree weather. It was 40 degrees at noon, so I am guessing the temperature at 8:30am. When we left at 9:30am, I happened to be behind him.

When the owner turned left at the intersection, I noticed a heavy amount of white smoke coming from the exhaust pipe and when he accelerated into the straightway, the heavy white smoke became stronger. I checked all of the other cars moving with him and in front of me and there were only slight mists or wisps of white smoke coming from their exhausts.

According to your posts, it could either be a blown head gasket or a modulator diaphragm. I don’t have it around to do an oil check (chocolate milk shake consistency) nor do I know if the antifreeze is low.

I called the mechanic and asked him to do a compression check again. I did not know about the Coolant Pressure Check you spoke of. He said that he would do an emissions test, and he could tell from that if it is a head gasket or not? Is that true? I checked your site for emission test results, but couldn’t come up with an answer.

Anyway, I called the owner and asked him to return the vehicle for this test. He never showed. Perhaps he was busy, or maybe he is putting in that Coolant Leak Sealer you were talking about before he takes it into the mechanic.

The owner is mechanically inclined – he has rebuilt a Model T and also is refurbishing an old Lincoln Towncar. He has done much of the work on the Roadtrek himself. My next question is, if he is putting in a Coolant Sealer, is there anyway to tell he did? Is there a test for that?

I am a little paranoid right now. The owner is asking $10,000 for this motor home which is in my budget range. I don’t have a lot of money, so I sure don’t want to buy a vehicle that I have to put thousands more into.

Sorry to ask these questions direct to you, but after I signed in as a new register and confirmed my email as a new register, I still couldn’t post. It said not able to post or something like that on the bottom right of the page.

Thank you so much for having this site. I will definitely bookmark it for future reference.



Well hello there Susan,

I would avoid ANYTHING that is smoking from the exhaust pipe….you might soon know why the current owner is parting with the vehicle. White smoke is usually due to coolant getting inside the combustion chamber of the engine…and it should not be there.

I would get a cooling system pressure test done, or the emission test…., actually I would do BOTH. The emission test can tell you if there is too much oil or unburned fuel in the exhaust as well, which would be helpful information at that mileage interval.

The coolant pressure test would be helpful as well, to check for internal and external coolant leaks in the system….like a head gasket problem. I would take this vehicle to a real RV repair shop and let them do both tests for you along with any other “used vehicle inspection” they offer. That would be money well spent!

Keep me posted as to what you find out please.


Austin Davis

Reader follow up

Dear Austin,

I guess the decision has been made for me. The owner took a flashlight, the mechanic left in the van, back to the mechanic on Monday. The mechanic told him that I wanted a coolant compression test besides the emissions test and that he had an opening this Thursday to do it.

The owner said that didn’t fit into his schedule, but didn’t attempt to make different appointment. I called the owner this past Saturday, left a message on his voice mail, but as yet, he has not returned my call.

Now if I was trying to sell an RV for one year and I had a serious buyer like myself, I would do whatever it took to sell the thing. Either he knows about the head gasket problem or is more interested in getting to Florida than selling it. So I guess he has chosen not to sell it to me. Problem solved….

Thank you very much for your input and personal attention. I will try to use the web site next time I am scared out of my wits about a purchase. You saved my life, so to speak!!! I am genuinely appreciative of your professional advice and will spread the word about your sites. If anything else happens to come up with this drama, I’ll let you know.


Posted in: Over Heating

Got Something to Say?