phil w

[phil w]

hello,
we have a '91 240 f/inj volvo 2.3. on cold, damp days it emits a huge amount of exhaust vapour. had it checked by experienced mechanic. no obvious problems. no oil or water loss. good fuel consumption. anyone experienced similar problem? is there a fault? is there a cure? any help greatly appreciated. phil w. p.s. i see no other 240's doing this in similar conditions- it really is a lot of vapour

[stephend]

My 740 is similar. If you're not losing coolant, then it can't be a head gasket problem. And if the engine is getting up to normal operating temperature, then everything should be ok.

My theory - though I'm probably completely wrong! - is that the exhaust pipe is so long on these cars that the exhaust has cooled enough for the water vapour to form steam at the tail-pipe. Also, I have a hunch that catalytic converters help to reduce the amount of steam at the tail-pipe, because of the temperature they run at, and we're so used to that now that the steam from a car without a cat (I'm guessing yours doesn't have one?) comes as a surprise.

[Volvon]

My 240 used to do the same, although it was a carb model. Turned out it was running too rich (excess fuel makes grey smoke). I just dialed in the adjustment screw on the carb and it lessend the grey smoke not sure how you adjust the injection models. But fuel for thought....

[phil w]

Many thanks Stephand & Volvon for your help. Our model does have a cat. and I'm wondering if there's problem with that and/or the Lamda sensor. There's no grey smoke, just huge clouds of vapour- enough to fill the rear view mirror! One other thing - on cold start-up it's fine, only when temp. rises does problem happen and it continues when engine is hot. Strange.

[stephend]

I suspect it's fine, especially if your mechanic has given it the thumbs-up - just keep an eye on it...

[MikeGMT]

Could possibly be a lot of water collected in the silencer/back box.

Mike

[mikealder]

Does it still throw steam out after a 100 mile blast down the Motorway as that should be enough to dry out the wadding in the silencers.
Moisture will build up in the exhaust especially if lots of short trips which never get the exhaust up to a hot enough temp to clear the water out - Mike

[phil w]

Thanks Stephand & MikeGMT, I'll get the exhaust boxes checked. I'm not losing coolant so there must be water somewhere. Thanks again, Phil

[phil w]

Thanks mike, I do a lot of short trips- sounds like there is a build-up of water in the exhaust. I' ll give her a blast down the M20 in the New Year ( might even take my fishing rod ). Thanks again to all of you for your help, Merry Christmas guys, Phil W

[david philips]

have a look at the water level is it going down if not then theres no water loss, the only other thing it could be if theres a turbo fitted would be a seal starting to fail.

in the winter my 940 is used on a lot of short trips and gives of a lot of white smoke or steam out the exhaust and has done for the last 10 years and as far as i know theres nothing wrong with it.