Posted by Peter Florance on November 12, 2001 at 14:42:37:
In Reply to: running rich. posted by Chris barnard. on November 12, 2001 at 14:04:18:
Not necessarily rich. When you pull the vacuum hose you also raise the fuel pressure by 7 psi or so.
Try pumping the brakes at idle to verify. If idle picks up, then it's definitly rich. Maybe bad coolant sensor (or corroded connections) or binding air flow meter if it's rich. Also could just be mixture bypass screw if it's only rich or lean at idle. If you blip the throttle to 3k and let go, if the rpms dip below idle and then rise, it's too rich at idle.
Remember mileage on 530 is going to be poor with stock injection (12-14 mpg).