Anyone able to suggest SMax engine fault? Engine failure warning with foggy/mist at rear of bonnet?

NeilF

NeilF

NeilF

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So twice now on a long journey our SMax has cut out with an engine malfunction warning. The garage looked at it after the first occurence and basically came up empty.

It happened again over the weekend (after 2hrs of driving):-
- Engine cut out/stopped and an Engine Malfunction was reported on the dash.
- A misty/foggy whitish vapour could be seen coming up from the rear of bonnet at the bottom of the windscreen.
- Engine is not over heating (at least according to temp gauge).
- Engine would restart but would cut out again randomly (even at idle) with Enginer Malfunction.
- Engine could then (at times) be lumpy. eg: When driving it onto rear of recovery vehicle it was lumpy and on the verge of stalling.
- Once cool/later it seems fine again, and indeed is perfectly drivable.

To me, the misty fog coming up at the bottom of the windscreen/rear of bonnet must surely be a significant bit of evidence as to the cause?

Any suggestions from knowledgable folks?
 
Vita said:
Run it with the maf sensor unplugged and see how it drives / idles.
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The car can be driven for weeks fine... ie: It's taken months for this problem to happen a second time.

So I could unplug something, but it might be weeks of driving until it does/doesn't happen?


The things in common seem to be:-
a) A long run (hours).
b) That misty/whitish fog from the rear of the bonney - Not a lot, but enough to see.

Surely (b) must point to something?
 
vanpeebles said:
Does it use a lot of oil?
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Don't believe so. We're certainly not topping it up, so it would only be done by the garage.

They checked it after the first occurence of this problem, and came up with the injectors being the most likely cause. But I don't understand how that would cause the white mist/fog coming from the back of the bonnet? Mind you, that is near the injectors I guess?
 
vanpeebles said:
Are you checking the level? :) Same goes for coolant? Is the mist oily? What does it smell like? Any idea what the plugs look like?
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I'll check the oil level, but no warnings have appeared for it.

The mist didn't look oily. It disappeared very quickly, but was visable just at the bottom of the windscreen ebbing and flowing (rear of bonnet). There was no sign of it later. eg: When I restarted the car and left it on idle and it cut out again with yet another engine warning.

Is it possible under the appropriate conditions its a leak from an injector? ie: It's a mist of fuel/air?

ps: I did notice the coolant looked low. Not sure if connected obviously...
 
You should always check your oil level :) Usually when warning lights come on, the engine will already be knackered. Especially when trying to track faults. What colour is the exhaust pipe? How does it smell when running? I wonder if it's oil or coolant vapours, maybe burning the stuff. I reckon if it was fuel mist, the mushroom cloud coming after would give it away :D
 
vanpeebles said:
You should always check your oil level :) Usually when warning lights come on, the engine will already be knackered. Especially when trying to track faults. What colour is the exhaust pipe? How does it smell when running? I wonder if it's oil or coolant vapours, maybe burning the stuff. I reckon if it was fuel mist, the mushroom cloud coming after would give it away :D
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If its a coolant mist, then what could cause that? A leak somewhere? There wasn't much of it and it seemed very much located around the bottom of the windscreen area.

Exhaust looked OK. Engine oil looked ok - Not milky.

There was possibly an odd smell after the first occurence, but didn't notice it on second. So not sure.

Note: Why would that cause the engine cut out and engine warning due to coolant? - Note: Engine showed no temperature issue according to dash.
 
vanpeebles said:
The coolant could be getting into the burn cycle of the engine, and making it run rough etc. How low is low coolant? :)
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It was down to just an inch or two (instead of 4-5).

I'll contact the garage to see if they checked it after the first occurence - which you would have though they would have.

So that could mean as you suggest the coolant is being lost? But why would that make an engine warning light come on?

ps: Thanks BTW!
 
How is the level now, compared to LOW/HIGH. Is it below low? For the warning ligtt, it could be that it knows something is not quite right in the running on the engine, the ignition could be affected. Is it a diesel or petrol?
 
vanpeebles said:
How is the level now, compared to LOW/HIGH. Is it below low? For the warning ligtt, it could be that it knows something is not quite right in the running on the engine, the ignition could be affected. Is it a diesel or petrol?
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I'd need to check again.

But at the weekend it was definately very low. I emptied a small bottle of water into it, just to make it more of a "comfortable" level. I didn't put much in so as to upset antifreeze mixture etc.

This is a diesel.

I suspect I could get in the car now, and drive it 50 miles with no problem... But at somepoint, the same would happen as has now happened twice before.


So if we take two things:-
1) Low coolant?
2) An odd mist/vapour/fog at rear of bonnet?

Then the question is what would these suggest along side the engine cut out/malfunction warning? And some lumpy running soon afterwards?
 
If you drove it 50, would the coolant drop? Any sign of any leaks etc? Ran your hand round all the pipes and fittings? Usually coolant has a strange smell, and you can smell it leaking onto a hot engine.
 
vanpeebles said:
If you drove it 50, would the coolant drop? Any sign of any leaks etc? Ran your hand round all the pipes and fittings? Usually coolant has a strange smell, and you can smell it leaking onto a hot engine.
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Don't know...

All I can say is the garage had the car after the first occurence. And when it happened a second time the coolant was very low. I'll see if they can confirm they checked it. If they did then clearly it's dropped quickly.

I would say at least at one period there was an odd burny/odd smell on the first occurence. Didn't notice it on the second.
 
vanpeebles said:
Are you using the car now? If so we need observations of levels etc :)
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Nope.. Car was returned via recovery truck and has remained on drive since.

Guess I could ensure coolant is topped to max, and start using it again at least for local journeys. But there's no way I'd use it for any sort of long trip again at the moment...
 
Possibly crankcase breather is blocked and causing pressure which gets released as it blows by the blocked breather?
 
acemastr said:
Possibly crankcase breather is blocked and causing pressure which gets released as it blows by the blocked breather?
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Whoa that's Klingon to me....

And that could account for possible drop in coolant and the fog/mist when Engine Malfunction is reported?
 
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