AUXR6VCT probs

[2fellas]

hi all i have a 200 au2 xr6vct that has a bad idle problem and now it seems to have an issue were the revs go up and down on there own , not a lot but a couple of hundred revs and when is idling its quite obvious .its different to the rough idle problem though
i have replaced fuel filter ,air filter ,spark plugs and leads and its getting worse ..its like sitting in a mildly worked v8 thats how rough the idle is .when your at the back of the car you can a backfire/pop in the exhaust as well and when you start the car it beeps 3 times..like beep beep beep a pause then beep beep beep does that three times

any ideas ,its still a great car and goes well

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