164 2.0 liter twin spark question

[briertyj@xxxxxxx]

     I am posting this question on behalf of a friend who has a problem 
     with engine idle speed. The car is a 1991 2.0 Lusso version.
     
     The normal engine idle speed is about 900 rpm. However quiet often  
     this "hunts" up and down around this figure in a wave pattern. 
     i.e up to 1500 and down to 700. 
     
     He was convinced this was the idle control valve so he obtained a 
     couple of used units from a breaker. Unfortunately this has not solved 
     the problem.
     
     Would any digest members be able to offer any suggestions as to where 
     he should next look ?
     
     
     John Brierty
     
     
     Dublin
     Ireland
     
     
     
     
     
     
     

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