2003 Fiesta - air-con causing shudder

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Fri 20 Apr 2007 15:49
2003 Fiesta - air-con causing shudder - howy868
Some 6 weeks ago we had the air-con radiator /heat exchanger replaced after a front impact with motorway debris. The air-con seemed to work OK when we tried it briefly after repair. However, now we are using it regularly, switching it on causes a series of random short vibrations which usually cease after 2 or 3 minutes of running. Engine idle speed drops considerably during each vibration burst. I also believe that we are only getting a small chilling effect from the air vents.

Coincidence or related to the repair?? the repair comes with a 3 year guarantee if the problem is proven to be related.

Thanks in advance
Howard
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Fri 20 Apr 2007 17:12
2003 Fiesta - air-con causing shudder - jc2
When you turn on the A/C,there should be a momentary drop in revs(and I mean momentary)till the idle speed control valve corrects-anything else is not correct.
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Fri 20 Apr 2007 17:15
2003 Fiesta - air-con causing shudder - bell boy
might be the electric fan running out of true causing vibrations
in any case as said its not right and wants looking at before it becomes very expensive bro
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Fri 20 Apr 2007 17:31
2003 Fiesta - air-con causing shudder - injection doc
As Bell boy say's check the fan to make sure its working & not out of balance but I suspect the system has too much gas in it and the pressures are building up high putting a load on the pump & making the engine surge, having said that the reverse can apply & if its low on gas you will also loose the cooling effect & after 2-3mins of running the pump will be continually cutting in & out also making the car judder. Get it back for a pressure check
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Mon 23 Apr 2007 21:22
2003 Fiesta - air-con causing shudder - wrightstuff
Sounds like the system may have 'air' in it due to not being correctly evacuated and re-charged. That would cause the problems your having. If they have simply just charged it up then air will be present and will cause excessive compressor discharge pressure and little cooling.
If this is the problem it needs sorting asap as the air will turn to water & ice at certain places which will block / corrode the system. Also if it's had new parts fitted have they been kept clean and dry? Mechanics are notorious for having filthy hands on the job. Could have got some grit or dirt etc in the system?
In my experience many of these garages which have suddenly become 'air-con specialists' overnight know little about the basics of refrigeration and air conditioning and usually just use an all in one machine which does the job for them........until it packs up !!
I'd be asking a few questions when i took it back about the repair job etc.
Hope this helps, would be interested to know how you get on.
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