Thursday, April 26, 2012
The Fiat 500 Abarth has been gone over from stem to stern to make sure it delivers reliable performance, whether on a racetrack or on your local commute. These cars receive heavy use in Europe on the racetrack during track days and club events, not to mention being run flat out on the Autobahn (and Autostrada when no one is looking). One such feature of the Fiat 500 Abarth that helps guarantee reliability is an after-run coolant pump (ARCP) that circulates coolant through the turbocharger's housing to cool down the turbo when you turn the car off. Here is how it works:
The after-run pump is used to circulate coolant though the cooling system when the key is off and a predetermined temperature is reached. The primary reason for the pump is to help cool the turbocharger to help prevent damage due to heat soaking. The after-run pump is free spinning in the Key ON, Engine ON condition and activated during Key OFF, Engine OFF condition for up to 10 minutes. The pump draws coolant in from the thermostat housing and sends it to the turbocharger when activated. The Powertrain Control Module (PCM) controls the operation of the pump. The inputs to determine pump operation include engine coolant temperature, throttle position and engine off time.
On the 1.4L turbocharged engine, there is an after-run pump (4) located on the right inner fender, bolted to the front of the shock tower (1) . The after-run pump has an electrical connector (3) and two coolant hose connections (2).
So, that noise you hear when you turn off your Fiat 500 Abarth is your friend, the after-run pump, keeping things nice and cool for your next run!
Description and image courtesy of Chrysler LLC