Steam from exhaust...Why do some cars have more than others?

[sgtbash]

I thought it was just my Supra. Seems to produce so much steam I get paranoid over it!

[Ozzie Osmond]

williredale said:

It was just a portable fog machine.

Hawkwind's tour bus?

[Defcon5]

Got to be honest, I like looking in the mirrors to see big plumes of steam coming from the exhaust.

[Seesure]

After 10 minutes it will literally drip out of the exhaust pipes....

[Matt UK]

Benbay001 said:

williredale said:

I thought mine was bad one morning until I pulled up behind an XKR.

It was just a portable fog machine.

"They all do that, sir"

When i clicked on this thread i was thinking of my old S Type R

Must be a Jaguar thing as my XJ did this. When warming up, I get it. But even when the car had be driven for an hour, sit in traffic and it continued to plume.

[R12HCO]

My 525i is stupid for this.

[rayyan171]

Seesure said:

After 10 minutes it will literally drip out of the exhaust pipes....

Now the cold weather is here, mine always seems to smoke!
But, it's not an M5(528i)

[DukeDickson]

Focus ST is yet another sinner on this front.

[*Al*]

Mine steamed like Didcot power station.

[31mph]

The cold weather thing's simple - It's the same reason that when you breath out in cold weather you can see it

[996TT02]

Petrol when burnt produces co2 and h2o.

In cold weather the h2o which for obvious reasons is produced in the engine as vapour, condenses when it meets the cold outside air.

Or the cold metal of a cold exhaust, resulting in drips from the tailpipe till everything is warmed up.

"more" or "less" visible depends on many factors I suppose but from the above you can work out which may apply.

[Tom H]

My Golf R32 is bad for this, almost makes it hazardous when reversing off my drive

[kentmotorcompany]

996TT02 said:

Petrol when burnt produces co2 and h2o.

In cold weather the h2o which for obvious reasons is produced in the engine as vapour, condenses when it meets the cold outside air.

Or the cold metal of a cold exhaust, resulting in drips from the tailpipe till everything is warmed up.

"more" or "less" visible depends on many factors I suppose but from the above you can work out which may apply.

So diesel when burnt produces less h2o than petrol?

[anonymous-user]

*Al* said:

Mine steamed like Didcot power station used to before it got shut down.

Tune in next week for more power station news!

[stedale]

sgtbash said:

I thought it was just my Supra. Seems to produce so much steam I get paranoid over it!

At least yours isn't a 7m nothing steams as much and it's probably fubar to boot

[RumbleOfThunder]

It's not a question of a hot/cold engine but hot/cold exhaust. After a long run when the whole system is toasty, there'll be no "steaming".

[vit4]

V8covin said:

Every car I've ever owned seems worse than everyone elses lol

Same here the older (pre-cat?) cars seem worse as well

[skyrover]

rover v8 is pretty bad for this...

Even after shutting it off for just 10 mins, as soon as you fire it back up out comes clouds of vapour.

[otolith]

The amount of water vapour coming out of the back is directly proportional to the amount of fuel going in.

[dirty_dog]

RumbleOfThunder said:

It's not a question of a hot/cold engine but hot/cold exhaust. After a long run when the whole system is toasty, there'll be no "steaming".

My 530i does it all the time but a few other BMW sixes in this thread has out my mind at ease
I suppose water vapour disperses but smoke not so much.