Early morning fog

Technical questions and answers about the Mazda Bongo

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Anonymous

Early morning fog

Post by Anonymous » Tue Dec 19, 2006 3:52 pm

When I start up from cold, my Bongo spits out a cloud of blue smoke for about 30 seconds. The van also shakes as if its about to cut out. However, a quick rev and all is fine. Can anyone let me know what the cause of this may be?
Veg_Ian

Post by Veg_Ian » Tue Dec 19, 2006 4:12 pm

Are you sure it is blue? Blue smoke is usually bad news and is usually an indication of oil being burned in the cylinders. A compression test would help confirm this.
Anonymous

Post by Anonymous » Tue Dec 19, 2006 4:18 pm

Would there be any other symptoms? Under normal driving conditions there appears to be no other problem
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dandywarhol
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Post by dandywarhol » Tue Dec 19, 2006 4:40 pm

If its bluey grey it the old favourite - faulty glow plug(s).
Plenty of info in the search facility blue(grey)adarron
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David Edwards
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Post by David Edwards » Tue Dec 19, 2006 7:36 pm

When did you get it serviced last, could just be dirty plugs, got to start somewhere see havent you, might as well be the plugs. Happy motoring.






I have trouble with dilec...dislek, diselec..spelling sometimes, must be dyslexic, never got any prezzies at christmas, seems I kept sending my letters to satan. :lol: Happy motoring.
Colin Lambert

Post by Colin Lambert » Wed Dec 20, 2006 1:05 pm

I have trouble with dilec...dislek, diselec..spelling sometimes, must be dyslexic, never got any prezzies at christmas, seems I kept sending my letters to satan. Happy motoring.
David,
Good job you don't live in Ipswich then! (see Bad Jokes......Where's it gone.)
Last edited by Colin Lambert on Wed Dec 20, 2006 1:09 pm, edited 1 time in total.
fordavefreda

Post by fordavefreda » Wed Dec 20, 2006 1:05 pm

funny that i was about to post a question about the same thing!

mine starts pefectly and runs fine on tickover, but as soon as i shift into drive it coughs and splutters until i rev it then i get the cloud of greyish smoke come out. it then is fine, i've tried warming the plugs twice( turning on the ignition and waiting for the plug light to go out then again) but this doesn't seem to make a difference. i ve even sat with the engine ticking over for a while then shifting into drive but no difference, it always seems to be that initial increase in revs that causes the problem, only happens when cold and only in recent cold weather. any more ideas?
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dandywarhol
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Post by dandywarhol » Wed Dec 20, 2006 2:07 pm

Although the glowplug light goes out on the dash the plugs are kept on by a temp. sensor connected to the glowplug relay. They can be kept on for several minutes (depending on the coolant temperature).

If the plugs aren't up to their job then they'll breakdown under load (driving off) until the cylinders are up to temperature and able to self ignite the vaporised diesel.

I've wired an illuminated switch into the circuit (courtesy of details on a factsheet :) ) which manually turns off the plugs whenever I feel the engine can cope by itself.

The prolonged use of the glowplugs is a Japanese market requirement to ensure a cleaner exhaust.
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Veg_Ian

Post by Veg_Ian » Wed Dec 20, 2006 2:16 pm

Dandy - I'm confused about the colour of the smoke. If the fuel/air mix wasn't burning properly then I would expect black smoke ie. unburnt fuel. Blue smoke usually means burning oil ie. oil in cylinders or in turbo feed. Why blue smoke if glowplugs have gone bad?
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Post by dandywarhol » Wed Dec 20, 2006 2:50 pm

I agree with you about black Ian but I think whats happening is that its a bluey -grey combo of partially burnt fuel and water vapour.

The reason I know is that mine is doing the same on cold mornings - just need to get psyched up to replace the plugs sometime soon :wink:
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Veg_Ian

Post by Veg_Ian » Wed Dec 20, 2006 3:07 pm

Ok - mind you as my morning starts at 6.30 I would be lucky to see any smoke at all, never mind the colour on these dark and gloomy mornings :)
fordavefreda

Post by fordavefreda » Thu Dec 21, 2006 8:06 pm

so the plugs stay on when the engine is running to a certain temp? i'm a bit confused as when the ignition is turned on and the light goes out the plugs are up to temp so switch off, i think this coz if you leave on the ignition for any period of time it seems like the plugs have cooled down as the engine won't start until you turn off the ignition and on again for the plug light to go out again? :? hope this makes sense, i guess it's obviously a glow plug problem that 'll have to tackle in the near future
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Post by dandywarhol » Thu Dec 21, 2006 11:26 pm

You'll hear a "click" when the relay stops feeding current to the glowplugs. When you're driving you might hear a "click" when you lift off the throttle - that's the plugs cutting in again, controlled by manifold vacuum until the coolant has warmed enough. The reason I know this (apart from reading it here :lol: ) is I've got an l.e.d. in the cut out switch I fitted and it lights whenever the glowplugs are on................ :roll:

does this mean I've got bling???????
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fordavefreda

Post by fordavefreda » Fri Dec 22, 2006 5:55 pm

i' ve always wondered what that click was :? sounds a bit like when you click on things with your mouse on computer :lol: , will get the plugs sorted after chrimbo, how much are the plugs for a set?

cheers for help and have a proper bo chrimbo everyone :wink:

dave
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Post by Dabs » Fri Dec 22, 2006 6:04 pm

Ive wondered about that clicking noise as well,thanks Dandy another little query cleared up!

Cheers Dave
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