Excessive exhaust vapors?

[grumpy]

My 2011 Pilot seems to have excessive exhaust vapors now that the temperatures are 40 and below. My driving mostly short distances and parking outdoors probably contributes to the exhaust vapors. Nevertheless, they are so pronounced that when accelerating in to 55 mph traffic (after only a 1/4 mile drive from first starting the vehicle) I cannot see anything behind me and have to use the rear wiper to remove the condensation from the window.

I drove my 2004 Pilot for 100K+ miles under the same situations and did not have this "problem". Perhaps since the 04 only had a single exhaust and the 2011 has duel that is the reason for the difference?

I have not added coolant but some may have been added during oil changes without my knowledge. It has been suggested a head gasket coolant leak could be causing the excessive vapors.

Any feedback or suggestions would be appreciated. I'm at 26k and don't want to go past the warranty if people think I should take the Pilot to a dealer. Incidentally, the dealer told me if there was a problem I would have the "check engine light" on.

[rocky]

Under warranty make the dealer fix it.

[PilotVlad]

Are you talking about steam or smoke? There's a big difference. When temps fall, it takes the catalytic converter(s) longer to come up to temp so the exhaust will smell worse until that point. Low temps and high humidity will also result in the car producing steam longer than in higher temp and lower humidity conditions. Coolant leaking into the combustion chamber will present itself as white smoke - not steam - real smoke.

I don't agree with the dealer about the check engine light. It would take a while before the oxygen sensors throw a code. By that point, the cats have either failed or near failure and you've probably damaged engine internals if you really were burning coolant.

Edit: Let me also add that you'll burn more coolant as the engine gets warmer and the cooling system pressurizes. So you'd see much more white smoke running hot vs. cold.

[RSQ Pilot]

are you driving in heavy traffic? Fresh air intake may be allowing other's exhaust to enter ....

[1YESfan]

Winterblend gas blows as well. Get it looked at or have a dealer mechanic take a ride with you while you are under warranty. Now is the time for any of your concerns.

[AndyC]

My 2012 does the same thing. IMO, it's a combination of water vapor from a warming exhaust system, aerodynamic qualities of a station-wagon-type vehicle, and Honda's styling decision to have extended dual exhaust tips pointing straight out the back and exiting almost parallel to the edge of the rear bumper. The exhaust pipe of the pre-2009 model exhaust system doesn't seem to extend as far back, and the 2008 Pilot VP in our family doesn't seem to have this issue.

Ever see airflow studies performed on a station wagon or SUV-type vehicle? The air flowing over such a vehicle stalls and swirls and churns around the rear window/bumper area. That's why the rear window of such a vehicle gets very dirty in messy weather. This characteristic is pulling up moist exhaust vapor and allowing it to contact the back window, thus the fogging effect in question. The cure would be to route the tailpipes to terminate on the sides of the vehicle, just behind the rear wheel, which would allow the exhaust to diffuse a bit before reaching the very back of the vehicle. Many older station wagons had their tailpipes configured in just that manner.

[grumpy]

Thanks for the answers/suggestions.

It is vapor not smoke being exhausted. There is no other vehicles exhaust adding to mine. The position of the exhaust tips does make sense concerning the window moisture.

The nearest dealer is 80 miles away. To have them see the problem would require me to leave the car overnight so they can drive it when the car is cold the next morning. Thus, I'd need my wife to follow me to bring me home and vice versa. I guess I was hoping everyone's opinion would be my experience is normal. One of the problems of living out in the sticks far from a Honda dealer.