Heat riser is operated via rod connected to vacuum pulloff, vacuum is supplied from EFE (early fuel evaoration) ported vacuum switch on intake manifold near water neck. As it sits now, I need vacuum immediately after startup to close heat riser to direct heat across my intake to aid warmup in cold weather. Problem is majority of vacuum switches are normally closed and do not open until warm, this really has me scratching my head.
2007-11-07 04:27:43 · 2 answers · asked by Anonymous in Cars & Transportation ➔ Car Makes ➔ GMC
The actuator should be closed when the motor is running and the motor is cold. As the motor heats up the actuator will have its vacuum vented by the switch and it will open. When you shut the motor off the vacuum will vent no matter where it is and the valve will be open.
2007-11-07 06:14:18 · answer #1 · answered by Deano 7 · 1⤊ 1⤋
dont see anybody else trying to show how intelligent they
are so here I go ..........he's right ..give him 10 points
2007-11-11 09:20:47 · answer #2 · answered by james a 3 · 0⤊ 0⤋