GQ Voltmeter & dash lights on start up

[dirtydog16]

G'day all,

I have a 90 model GQ diesel Patrol and when I start the car the voltmeter goes from low then jumps to a normal level and then repeats this for a little while until it stops after a little bit of time.

The dash lights also dim and brighten with the voltmeter going form high to low. There also sounds to be a clicking noise that can be heard when the voltmeter needle goes up and then down with the dash lights.

In the end it does stop and the dash lights stay fine in the end and so does the voltmeter but it is bugging me and I would like to see what I can do to fix it.

I had a bit of a search becuase I thought I had seen something like this on here before at some time.

Any help / suggestions would be appreciated.

Thank you,

[chimpboy]

Sounds like glowplugs maybe? But I am not a dieselish person.

[stuee]

When you say starting, do you mean while the starter motor is turning or immediately after the engine has fired up?

[dirtydog16]

When you say starting, do you mean while the starter motor is turning or immediately after the engine has fired up?

Hey mate,

After the starter motor has finished and the car is running for the first minute or so.

After the first minute or so it goes to where it should be and the dash is as bright as it should be and my battery charges as normal I believe.

I think it may be something along the lines of when the car starts the electrics just seem to be running on the battery only and the alternator kicks in making it all good and then kicks out and it goes back to the battery with less charge so dimmer than the feed from the altenator.

I have a new battery and alternator and all my battery earths are good thick, clean and tight. I had this problem before i changed my alternator and battery and it is still continuing now with the new ones although I did not change them to fix this problem.

Cheers

[dirtydog16]

Sounds like glowplugs maybe? But I am not a dieselish person.

Hey mate,

I am not sure about that as the car starts and runs perfectly everytime, it just seems to be relating to the alternator / electrical system.

Cheers

[its aford not a nissan]

its your glow plugs warming up ,

that is all

[stuee]

its your glow plugs warming up ,

that is all

This one stumps me. How do the glow plugs warming up after the engine is already fired up cause the voltage to fluctuate?

[-Scott-]

its your glow plugs warming up ,

that is all

This one stumps me. How do the glow plugs warming up after the engine is already fired up cause the voltage to fluctuate?

Guessing there's some controller turning them on and off until it's satisfied that the engine is warm enough.

Doesn't sound right to me, but I'm not dieselish either.

[its aford not a nissan]

well on my car they will click in and out a few times for 30 or so secs after start up , they dont just glow for 10 secs and stop , they glow automaticly a few times , and for the voltage fluctuation ...... they draw a crap load of power each time they glow

[stuee]

We'll you learn something new everyday. Seems a bit odd to me but meh.

[GeneralFubashi]

Its the glow plugs alright, there isnt much on a diesel that will use that much energy. My smokin' hot diesel gemini keeps the glow plugs running on 1/2 power or so for 30-40 seconds after the engine starts to make sure its firing on all cylinders when the engine is cold. If it doesnt it splutters along on 2-3 cylinders for a while until it all heats up. New tech... gets the heart racing!