high hc emissions? Renault 9

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Mon 1 Sep 2003 20:21
high hc emissions? Renault 9 - lucky
I have a Renault 9 (auto, 1988,1397cc)that has been lying on my driveway for the past 2 years. It passed the MOT first time in September 2001. Have have spent some time preparing it for another MOT. Last week it only failed on exhaust emissions: \"HC high\". The guy at the MOT station told me that it could need anything \"up to a new engine\". The car is in excellent mechanical condition and I want to keep it as a run around. Question is what does \"high HC\" mean and what is the likely remedy? I want to take it to a local garage for an opinion but would like some information about this fault so that I know what I am talking about.
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Mon 1 Sep 2003 20:27
high hc emissions? - Sooty Tailpipes
High in hydrocarbons, this is unburned or incompletely combusred fuel, or burning oil.

I presume you have changed the oil before the MOT?
What about the fuel?
Could be all sorts of engine-related things really!
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Tue 2 Sep 2003 06:35
high hc emissions? - Andrew Moorey (Tune-Up)
Not much to add really, usually the cause for really excessive HydroCarbons is a misfire. You would havee noticed if a cylinder had failed completely (I hope!) but a misfire caused by too weak a fuel mixture affecting all the cylinders randomly is a little harder to spot. Case for an engine tune methinks. (Yellow Pages; Car Engine Tuning and Conversions.)
Andrew


Simplicate and add lightness!
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Tue 2 Sep 2003 07:58
high hc emissions? - jc
Book it into a garage somewhat further away than your local one;then you can legally give it a good fast drive and get the whole engine,especially the oil really hot.If you had to start it after two years petrol was probably running down the bores and diluting the oil.
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Tue 2 Sep 2003 09:42
high hc emissions? - Altea Ego
how high was high? was it a lot over or just a tad?
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Wed 3 Sep 2003 21:26
high hc emissions? - lucky
Thanks for the replies. The MOT garage did not elaborate on how high it was. However I was thinking about jc's suggestion and try giving the car a good drive as it has not been driven any distance at all.
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Wed 3 Sep 2003 22:31
high hc emissions? - Altea Ego
Thanks for the replies. The MOT garage did not elaborate
on how high it was. However I was thinking about
jc's suggestion and try giving the car a good drive as
it has not been driven any distance at all.


The MOT garage have to give you a printout of the results. If it a few nats thingies over a good thrash of the engine when warm will clean it up, if its a lot over then there is another cuase.

Tell us the results from your printout.

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Thu 4 Sep 2003 12:56
high hc emissions? - pettaw
Thanks for the replies. The MOT garage did not elaborate
on how high it was. However I was thinking about jc\'s
suggestion and try giving the car a good drive as it has not
been driven any distance at all.



And from the tone of your reply you haven\'t changed the oil and filter. that\'ll only do good, and costs less than 50 quid anyway. Far less if you do the job yourself.
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