View Full Version : lights dim and flash when starting

12-08-2002, 10:22 PM
I think this is normal, and excuse my stupidity... But when my truck first starts in the morning, the lights flicker and Dim. Is this normal? Why does it do this?<br><br>Thanks Guys<br><br>Mike

12-08-2002, 10:35 PM
Yes it is normal in the colder weather. There is a grid heater in the intake that cycles on and off every so many seconds when the outside temp falls to a certain point. At least thats what I've been told 8)

12-08-2002, 10:45 PM
Mine does the same thing when it first starts and until I start driving. Itís normal as far as I know.

12-08-2002, 10:52 PM
This is due to the high power draw from the &quot;grid heater&quot; located on the intake side of the engine. (you will see two posts with rubber covered power wires on this heater, it's located at the base of the intake elbow where it goes into the engine, hence the warning sticker about starting fluid-never use it! BOOM...) This heater glows red hot and heats the incoming air to the cylinders to cut down on the smoke on start up, and allow the engine to start and run easier on startup. It goes off after a few cycles. NO worries. <br><br>See Ya...

12-08-2002, 11:38 PM
thanks,<br><br>I thought it was normal, I was just curious what made it do this. Thanks again<br><br>mike

12-09-2002, 10:34 PM
The heating cycle time will depend on intake manifold temperature:<br>15-59F degrees = 10 seconds<br>0-15F degrees = 15 seconds<br>below 0 F degrees = 30 seconds. <br><br>Jerry