ddhleigh

Basically it doesn't happen all the time. There are only two instances where when I speed up to merge into a hwy or onto a bridge that I noticed a small to moderate amount of exhaust cloud. I'm guessing it's the engine burning off the carbon or something.

On another note, on a cold start and the gas engine kicks in to warm up does it shake the car for you? Meaning while parked, it rocks the car when it turns on, but just that 1 time and doesnt happen again while driving. I saw another older post, but it was inconclusive.

Thanks!

added edit: Anyone here fill up gas without turning the car off? Was thinking about this the other day and logically the gas engine isn't on, just the electrical so it appears to be safe. However it is illegal in some provinces in Canada.

Droid13

Maybe you are referring to the white "water vapour smoke" on cold days when the vehicle is not completely warmed up. I notice this too, it does curl up the back window when accelerating briskly and seems to take a lot longer for this to disappear on the RX450h than most vehicles, even longer than my Camry Hybrid. I have wondered if it's related to the exhaust heat recovery system (something that was not on my 07 Camry Hybrid) cooling the exhaust gas / lengthening the time it takes the rest of the exhaust system to fully heat up and therefore producing visible water vapour longer.

ddhleigh

Thanks Droid13! I believe you're right. The cloud is white in color and not grey or black. So that is indeed a sign of water vapor.