my 207 Lucerne overheats. Replaced thermostat, cooling fans, water pump
on 2007 Buick Lucerne

engine still overheats. The A/C stopped working too. Runs OK on the interstate roads but overheats in traffic

Asked by for the 2007 Buick Lucerne
I had the same issue and it was a plastic fin underneath that deflects the air upwards toward the radiator