defender 2007 tdci cold start

Hi! in Norway we have a cold period with temperatures down to -20 deg. When i start my tdci when the temperature is about -10 deg. the engine start easily but after some seconds the engine crank a llittle before it gets it`s rhytm back. This happens several times with the same interval for some time until the engine gets some temperature. I think it is a defect glow plug that`s the problem. The glow plugs resistance is 0,5 ohms. It is not easy to disconnect each glow plug , but i have measured that the total resistanse is 7 ohms with a multimeter. This can not be true. Where is the fuse for the glow system located? What amp? I am very thankful for some help!

Hello,

Whats the anti freeze rated at your using ?

Its the car facing outwards into the elements or parked nose first ?

Lastly, have you put any diesel additive to make sure the diesel doesn't freeze ?

Glow plug resistance should be a lot less than 0.5 ohm, that only works out to 24 watts power. Good plugs should read 0.1 or 0.2 ohms, 7 ohms is no good. Are you sure your multimeter is accurate and if you short both leads together do you get 0.0 ohms?

I did a mistake . I did not disconnect the lead to the glow plugs while measuring. I maybe measured through the relay. I try again.

When you have finished measuring all the glow plugs resistance set your meter to voltage and see if there is power at the glow plug when you turn the ignition on. You will probably get 11 volts or so for 5 to 10 seconds. If the voltage is there you know the fuse is ok and the glow plugs should be working.

Then i measured again. I disconnected the lead from the terminal and it was 0,2 ohms. This means that with 12v it will use 60 amperes. Is 0,2 ohm to low resistanse?

Is that the resistance of each individual plug or the resistance of the lead supplying all the plugs? You need to measure each plug individually (with the lead disconnected from the plug) if you don't the good plugs will mask any dead plug.

If it starts I would say plugs are fine.
Sounds like diesel waxing?

It is impossible to disconnect each plug. My measurement is for all 4 plugs connected.Then i have to take the inlet manifoil away. Diesel waxing because of low temperature? Can i use parafin/kerosene to avoid this?

If you cant disconnect each plug then you wont be able to prove they are all working.

It is very difficult to disconnect each plug because of the inlet manifold. Maybe i have to use amperemeter to measure the total consumption? How many amperes should it be 4 x plugs 0,5ohm in paralell?

Theoretically about 20 amps per plug so around 80, you wont get the full 12v at the plugs because of losses in the cabling at that current

The glow plug fuse is 60a

In that case I would expect to see about 45-50 amps

I will lend an amperemeter to measure the ampere.