Technical New Member - Tech Assist Required please

[RacinGreen]

Hi, I've just joined, I have a '99 Mk1 Punto Sporting (my second) which I absolutely love. It has 74k on the clock (1 lady owner from new before me, so a rare car these days I think!) but the performance at low rpm has dropped off lately and the idle when cold can be erratic and too high by about 500rpm when warm. There is also a noticeable 'jump' in performance when moving away, sluggish to start with and then when you hit about 3000rpm she suddenly decides to 'go for it'. It feels like the ecu is struggling to sort out the fuel / air mix and only when it gets a decent shove does make it's mind up. The car cruises perfectly and doesn't show any signs of running hot at all. My hunch is a sensor, anyone out there have any experience of this, all suggestions gratefully received.

Thanks
RG

 

[SouLz]

Check air flow for any blockages or leaks. Could be the throttle body is gunked up causing uneven idle, or could be the air filter needs replacing.

 

[RacinGreen]

Much appreciated, will investigate!

RG

 

[fingers99]

Engine temp sensor, MAP sensor, pipe to MAP sensor all worth looking at, too.

 

[RaulCarnahan]

Compression test might also help

 

[RacinGreen]

Thanks all, will get on this asap!