BLK98GS3

hi everyone, i have a 98 gs300 with 70k on it. My car seems to smoke for a really long time after warming it up. I understand if it were really cold but this goes on even after i had been driving it for awhile and the car is completely warmed up, and i know its not that its not cold because i live in the bay area. Also after a long drive it smells like if something is burning. Im starting to think that my cat is going bad. Can someone agree or disagree with this and is it worth changing? when i bought my car i was getting about 18-19 mpg and i did a full 60k tuneup and was getting 20-22mpg....now its back down to 18-19 again...not a world of difference but i guess everything matters with gas prices today. Thanks for any help you guys can give me.

GWELEX

First, let's identify the smoke. Blue, black or white in color?

BLK98GS3

its white...ive checked all the fluids and what not and they are all fine...no fuel problems....thanks

chuckb

are you sure it's not steam? does it smell like anything?(coolant, oil, rich gas mixture)

GWELEX

White is moisture and it's more than likely a non-issue. I've seen cars running in warm temps (40+F) with lot's of moisture coming out of the exhaust, it's just part of the combustion process. Now if you car was running hot and the coolant level was falling you might have a blown head gasket or a cracked head. As the season warms up, I'm sure this will not be a problem anymore. Under load a bad catalitic converter will smell something like rotten eggs, pretty noticeable.

DASHOCKER

iTrader: (2)

Get an professional emissions cleaning done.

AZDesertGS

iTrader: (4)

Take a look at your oil and see if there is any water/coolant mixed with it.

JellyBean

Everything is possible in this world, but it's highly unlikely for your cats to fail without a CEL and a corresponding code. Your car has O2 sensors in the exhaust system whose only job is to detect ailing cats.

Don't assume the worst. Take your car to a reputable repair shop and get it diagnosed. I'm sure you can tell the difference between vapor and smoke, and it's the burning smell that worries me a little. Good luck.

BLK98GS3

thanks for all the replies everyone. At first i thought the burning smell was from a bag that was caught on the exaust pipes but that was a really long time ago. ill have it checked out. thanks again everyone

mikeyboy

could be some kind of a fluid leaking on your exhaust system.

NoS

I have the same thing. How often do you drive the car?

BLK98GS3

i drive the car everyday. If i just let it sit for 2-3 and drive it again, it will do the same thing and even though the temperature needle in where it should be the smoking wont go away for like 5-10 min

blacksc400

iTrader: (4)

Putting too much engine oil will also cause it to smoke. It just burning excess oil.

NoS

Yea you might want to check the level of the oil you have. Reason I asked about how often is I at times only drive mine couple times a month. I'm going to go outside and work on the cars so I'll check my level too (which most likely is normal)

NoS

And damn blacksc400 could you have any more Lexus cars!?