if it seems to pulse up and down prior to stalling suspect the PCV valve (its supposed to be changed every 20K miles)

Can also check my website where I have a huge section on idle problems

Mad Mole
Visit Mad Moles Mondeo Madness
2L Zetec, Cams, Stage 2 head, Valve work, Powerflow, Unichip, AEM Ram, K&N, Ecotek, 75mm Lower etc.
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