2001 SE, had a check engine lite, slight loping intermittently, but running well otherwise; scanned at Ford dealership - bad PCV pipe. When I drove away, the engine performance was nothing like it was, terrible, like missing a spark or two, near stall at idle; Service tech says they didn't do anything but physical inspection and scan. Are there any reasonable possibilities that something happened in the garage? The odds seem too extreme that I went from a decent performing engine one minute to one about ready to die AFTER being in a garage. Knocked off a vacuum hose somewhere maybe? (replaced both PCV hose which really was bad and vacuum hose coursing the top of engine to air intake chamber - also cracking at the U hose - but no difference in engine performance). Any similar stories with solutions out there? PCV valve seems ok. Advised that it might be cleaned but the piston action in the valve seems clear and clean.