Help! White Smoke from Exhaust

[jadelauren]

Got a 1.7 SDI and went to over take a car, down geared to 3rd like normal and the car completely lost revs and power and thick white smoke started coming from the exhaust of my car. Had to pull by and it eventually stopped after turning off the ignition. My car is needing an oil change quite soon (this weekend I'm changing the oil in her as it is quick thick and black at the moment). I got her back up and running again minus the smoke and she is randomly pumping out smoke whilst driving.

Possibly the head gasket on its way out (both mind and my partners thoughts) but wanted to know if anyone else has had this problem and what they think it is as I'm not the most mechanically minded person unless I'm physically under her or tinkering. I've to work in one piece but have to drive it home tonight 30 miles, any advice or thoughts?

[Karl_Mac_]

My immediate response would be head gasket. Is there any gunk/mayo under the oil cap?

[Cooper_GTI]

White smoke indicates water vapour, which, as said, is probably down to the head-gasket.

If the oil and water are still clear, then the gasket has blown between between a waterway and the cylinder. If it's drinking water, or the oil is yellow or the water is brown, then that'll give you 100% clarification.

[m1cr08472]

Check your header tank and oil dip stick. If its losing water and oil the Head gasket will be on its way out. It could be diesel fuel not burning right as well. I had a pug 106 that would blow white smoke, when first starting it up, cause the glow plugs had burnt out.

It could be a lot of things that cause a diesel to blow white smoke, glow plugs, injectors, fuel/air filter, compressor, head gasket.

If its still running you should be ok driving it home. I'd get it checked out as soon as you can though.

[Silver!]

I was going to say a new Pope, but it's a bit premature.

[Pete91]

Wish I could "Like" this comment ^^

[Defcon5]

Is it smoke or steam? Did it stink?

HGF is very rare in Lupos, I would suggest it is caused by unburned diesel for some reason. The random nature of the smoke would also support this.

[jadelauren]

Is it smoke or steam? Did it stink?

HGF is very rare in Lupos, I would suggest it is caused by unburned diesel for some reason. The random nature of the smoke would also support this.

Ah glow plugs, how can I test if it is that and not the head gasket?

[James827]

glowplugs are only for starting in the cold. don't get used whilst cars running or in warm weather really

[Cooper_GTI]

The one question you need to answer is;

Does it use water?

[jadelauren]

Is it smoke or steam? Did it stink?

HGF is very rare in Lupos, I would suggest it is caused by unburned diesel for some reason. The random nature of the smoke would also support this.

How would I test if it is un burnt diesel and not the head gasket as it seams to only do it under strain so when I'm on the motorway, dual carriageway, going up steep hills or overtaking so can get out and smell it really. It definitely looks like smoke and its been doing it again this morning.

It seams to be using the water out of the coolant tank too which I've been noticing over the past few days.

[James827]

how much water does it use? like how much are you putting in and how often?

also look for white is water stains around engine bay, particualy where there is a water pipe connection. could have a little leak!

Edited February 15, 2013 by James827

[jadelauren]

All sorted. Thank you everyone!

It ended up partly being the oil in my engine needed a change as well as the oil filter and also the fact up here we had dreadful snow, combined with going up hill and the guy in front of me stopping and my car getting stuck up hill wheel spinning for 3 hours and struggling it over fuelled. All sorted now though thank god its summer, goodbye snow!

[Silver!]

It's only February. Summer is still a good way off.

Glad you got it sorted though.

[jadelauren]

So after doing a full oil change and changing the fuel filter and many months later I find out that indeed it is my CAT that is giving up on me, a few weeks ago the exhaust started to smoke white fumes and cough out piles of black soot. Then gradually loosing power (running about 45bhp) and trying to stall when pulling off and feeling jolty. Then there was the rattle from the exhaust - After lifting the car in the air and having a poke about it seams the baffles have fallen in the CAT restricting the air flow therefore loosing power, feeling sluggish and coughing sooty deposits. Replacing the CAT tonight which will be bundles of fun!

[Skezza]

Why don't you decat until your next MOT?

[James827]

just bash the innards out, it will be alreet even for MOT aslong as thge chambers there. SDI's are pretty good on emmisions as it goes.

[jadelauren]

Why don't you decat until your next MOT?

just bash the innards out, it will be alreet even for MOT aslong as thge chambers there. SDI's are pretty good on emmisions as it goes.

Thing is it will be a right noisy bugger if I take out the baffles, it's just passed its MOT at the start of May so not too worried about that. Just don't want it rattling anymore and with getting a 409 grade stainless steel set up I'm hoping it will sound better. Plus just de Cat-ing a car isn't that easy I didn't think Skezza :/ I would need to weld in a cat spacer and then tinker about with the lambda sensor after ive removed the cat as it will just have a fit as it will only measure unburnt fuel

[James827]

you have no lambda sensor as its a derv, you just Cut and weld in pipe and it wont be that loud lol ive ran diesels with no silencer and they sounded fine. its not really a cat its just some filter to help stop soot, which you won t get much off as the fuelling is all electronically controlled.

removing the cat has no effect on fueling on these. aha

seriously just bash out the innards of the cat and put it back on, you will save yourself so much money and it wont really effect the car apart from potentially giving the exhaust gas an easier flow out

[lupoluke]

http://bit.ly/13lANRS

That would probably be the easiest option, and it's not a cat as such it's a Diesel particulate filter.

Your car will not fail emissions with a decat unless something is seriously wrong, it's more of a smog test than an emissions although I think the new rules are that If it had one fitted from factory then it should be there, although I think most testers wouldn't question this if it went through the test.

And as for noise you shouldn't even notice, I have just replaced the DPF and centre box on my tdi with a piece or stainless pipe and its hardly any different. I know there's a turbo to quieten things down but it would appear the back box keeps most of the noise away.

[jadelauren]

Doesn't matter really. Think most people by passed that I had already brought one and was fitting it tonight. Regardless, I don't want to bodge job my car as its just not how I am, changed the CAT on my drive this evening, only took a few hours. Not any good at welding so couldn't be arsed with that when I'd need a CAT anyway as it would fail MOT as it was made after 92. I know a few places that would pass it next year if I had welded a spacer in but I'd rather keep it OEM in that sense and keep it legal rather than cutting corners. Wasn't that much anyway, just less than £140 for the set up and nowt to fit on my drive. Immediately she's more responsive and smoother to drive. Quite chuffed. Thanks anyway guys but it was just an update.