1994 1.8 Petrol Mondeo with a lumpy idle - seems to increase then immediately decrease revs (constant looping) approx. twice a second, a sort of rythmic hunting. Revs only increase by 2/300RPM - not too noticeable on tacho but definitely very audible..
Also has a beauty of a metallic 'rattle' between 2250-2750RPM which, after reading
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AirInjection, has made me dread spending more money... So far I have changed the Idle air Speed Control Valve and the EGR valve (diagnostics machine said EGR fault but diagnostics machine's expensive!) with no difference.
Has anyone heard the noise when the Pulse Air Injection's faulty on these engines? Does it sound similar to a 'rattling' exhaust or maybe a heat shield? Does it rattle when hot AND cold and can it make the noise only between certain revs?
Thanks for any answers - have already spent too much on this car in comparison to it's value, but I need to get it running/sounding ok before I can sell it...