i just bought a 1999 f250 (look in my gallery) and when my father drives it, he ALWAYS forgets to wait for the glowplugs and i yell at him everytime. What harm will this cause to the engine?..and why does it even start?

as you can see..i know nothing about diesels..thats why i have FTE!! im learning slowly

 

unless it's below 40 degree's you don't need to wait.

 

even below 30 degrees,the mech told me that the glow plugs stay on for 2 minutes anyway.So i would have to say no it wont hurt it.

 

thats good to know..but then why does the light say "wait to start"

 

Cool,
I have been starting my 96 since I have owned it without waiting for the glow plugs. For one they don't work. I've tested them and all are shot. But here in Texas we don't need them very often. When it gets too cool, I just plug it in. The glow plugs just help the compression ignition when the temp is too low. The light is just a reminder that they are on so you can let them do their job. But it does not hurt at all to start it without waiting. But if it's cool and it's taking alot of cranking, you should wait. But on the up side, since all my glow plugs don't work, I have yet to change out my batteries, and it still cranks up right away. Everyone else I know around here has had batterie failure on their strokes. I figure I have less stress on them because they don't pull all that power for 2 min no matter what. Just my 2 cents.

RubberDuck

 

say, Rubberduck, when it starts gettin cold, doesn't it tend to smoke a LOT at startup? i know mine did before i changed the plugs....but you make a good point, who needs plugs in texas?

 

Its for the winter,so the piston camber has time to warm up,it also warms up the desiel coming into the camber.Its just made to help start the motor.
U can test it yourself with a test lite.

 

Doesn't hurt anything as long as it starts right up. As it gets colder, you will need to wait to give the glow plugs time to work, otherwise it gets harder and harder to start as it gets colder. I have a bypass switch in mine to keep them from coming on at all in the summer, and only once per day in the winter.

 

Red, yeah it smokes like a freight train until it warms up if I don't plug it in. But when I plug it in, it's not bad at all.

MDB, you have my attention! What, where, how do I put a glow plug bypass switch on my truck. I've been wanting to change the plugs out, but I keep thinking to myself what a waste for them to come on all the time and putting the extra stress on the batteries. I'm assuming something on the relay? Tell me more.

RubberDuck

 

Easy to do. Just install a switch of some sort in series with one of the wires that controls the GPR. When the switch is open the GPR obviously can't energize, even though the WTS light is on and the PCM is calling for the it. I used a toggle switch on the dash, and others use a push button that is only energized when they hold it down.

I also installed a dash mounted LED that is wired into the glow plug side of the GPR so that I can tell when it is actually energized. This is how I know that the glow plugs stay energized for a looooonnnnngggg time after the WTS light goes out, (if I leave the toggle switch in the ON position). Normally, when it is cold out ( around freezing) I will leave the toggle switch on for a good minute or so (long after the WTS light goes out), turn it off and then start the truck. It starts much easier this way then trying it right after the WTS light goes out, and by turning the glow plugs off before starting the drain on the batteries is greatly reduced. And once the truck is runnning, the glow plugs aren't needed anyway (except maybe to reduce emissions to keep the EPA happy).