Glow Plug

CRD4U2 · **Posted:** Mon Feb 09, 2015 8:31 am

Good morning everyone! I have a problem with the glow plug of my liberty 06, when I start it, the pigtail light stay on for maximum 2 sec. eventhought it is -20 degree celcius outside. It feel like it thinks it is 20 outside instead of -20 and by the way it was -36 this morning, didn't event think about triing it. I have a TDI and when one of the glow plug is not working the pigtail light will flash, does the libby has that too? Is there a sensor for temperature somewhere? Which fuse, relay and module are the one for the glow plug. Need help, will be selling the TDI pretty soon so I need to get the jeep back at 100%. And by the way it is my first liberty so I am not famillier with the location of everything yet.

diesel_guy86 · **Posted:** Mon Feb 09, 2015 8:42 am

That is normal, if there's a blown glow plug a check engine light (cel) will come on.

Several of us here ignore the glowplug light and wait for all the chimes and dingers to go off and then crank it. Better starting but these things still suck at cold starting. I can start on 3 plugs below 0°f on one crank but others have difficulty starting in 30°f (0°c).

Glowplugs are computer controlled, light will only illuminate for max of 2 seconds, but glowplugs can run up to 200 seconds depending on temp.

dirtmover · **Posted:** Mon Feb 09, 2015 9:15 am

Welcome to the forum. Your observation is normal. It should start OK at -36 but expect it to let off a lot of smoke and to be loud and rough for the first minute or two. It will smooth out dramatically after that.

No CEL = good glow plugs. Bosch do however state that their plugs lose potency with age which the ECU is not detecting.

I'd try starting it at that temperature first and then deal with any issues you notice. BTW, how well did it start at -20?

CRD4U2 · **Posted:** Mon Feb 09, 2015 9:48 am

At -20, It has to be plug in and it is very difficult to start. I have to try is 3-4 times and it rattle and smoke like a motherf*****r. Does it have an electric choke of some kind? Because I have to keep giving it gas to start it and to keep it from dying on me, if I don't give it gas, the RPM drop to 600-700 like if the engine was warm and it dies. When I start it, I give it some gas and it feels like it's not getting more even if I step on the pedal more, and it dies. When the engin is warm, sometimes it takes a couple of second to start, can it be the fuel filter that is getting clogged or air in the fuel?

CRD4U2 · **Posted:** Mon Feb 09, 2015 1:51 pm

Is it normal for the pigtail light to stay on for 2 secondes only when it is -20 outside and after I tried to start it, it doesn't even come on when I try again?

dirtmover · **Posted:** Mon Feb 09, 2015 2:26 pm

The accelerator pedal is simply an input into the ECU. Everything is fully electronically controlled.

For mine the rattling and smoke starts at just above -20 and gets worse at lower temperatures. The lowest I've started it will be just below -30.

Once started it only needs fuel and air to keep going. Sounds like you may have fuel delivery issues that are causing the stalling out.

The GP indicator is controlled by the ECU and is independent of the signal that is being provided to the plugs. 2 seconds on is normal but the GPs continue to burn long afterwards. For subsequent key turns the GPs are powered even though the lamp is not illuminated.

Check out the videos in this thread. They show the actual burn time versus the dash indicator:

viewtopic.php?f=5&t=78212

This vehicle has some great attributes but it in the Winter it sucks to the point that I don't even try to drive mine any more.

CRD4U2 · **Posted:** Mon Feb 09, 2015 3:26 pm

Thanks dirtmover for the info. When it will be a little warmer around here I will install a lift pump on it, it should help with fuel delivery.

Mountainman · **Posted:** Mon Feb 09, 2015 6:20 pm

It still starts rough with the block heater plugged in?

CRD4U2 · **Posted:** Mon Feb 09, 2015 8:27 pm

Yes and I tested the plug if it had resistance and it does. It will start but after a couple of try

Mountainman · **Posted:** Tue Feb 10, 2015 1:02 am

I'd reach in there and feel if it's getting warm. Someone else said that the upper radiator hose will also get warm after a few hours, but maybe not in extreme cold I'd guess.

Glow Plug

Who is online