Having occasional stumbling and stalling. Usually within 5 minutes of start up. One stall and its usually fine for the day. If i keep my foot on the gas it will get past the stumble. History of vehicle: 79 gle . 84 engine and 5 speed. Just about everything on this car has been replaced with in last couple years. Exception being the fuel pump . Head/valve job last year. All tune up items are new. Warm up regulator? Thanks in advance