Mystery warning light - Temperature gauge having a dance!

Adstar · Post by **Adstar** » 19 Sep 2006, 14:12

On a trip back from london I was alarmed to have a warning light start to glimmer and fade, then come on intermittently with progressive regularity!

During this time I noticed that the temperature gauge was bouncing around between normal and 80ish, but NEVER going much above its normal 90odd degrees.

Unfortunatly I haven't got a hand book for my 96 605 2.1td (If any one has one I would be VERy interested in aquiring it or a copy of!)

The warning light, located under the temp gauge, is orange with a picture of what looks like a fluid container with an inlet on either side and 1 on top. When I slowed from the motorway speeds I had been doing, the light eventually went out and stayed out.

I haven't had any other issues and can't see any leaks (on the ground or under the bonnet). Suspecting it to be the coolant level I was able to add about half a litre maybe more to the expansion tank (which hasn't been looked at for a few months).

I am after the identity of the warning light, and what the significance of the dancing tempe guage could be!

Thanks in advance.

OwenP · Post by **OwenP** » 19 Sep 2006, 14:30

Strange as this may be, the warning light sounds very similar to the 405 water in diesel light. Of course this may be miles off the mark

Adstar · Post by **Adstar** » 19 Sep 2006, 14:55

I have just picked my Jaw up off the floor! My headache appears to have doubled in intensity....

Water in Diesel?!

This opens up some more questions!

Is this suspicion (I know its not spelt right!) correct with regard to the warning light?
Where is the sensor that tells me there is this obviously worring contamination (So I have some idea of where it might be getting into, or picked up in the system)
How can you get water into the diesel?!

If it is watr in the diesel, then why would it be at high speeds, and not at low speeds?

I hope someone can tell me not to worry!

OwenP · Post by **OwenP** » 19 Sep 2006, 15:27

Like I said I may be miles off the mark. So don't panic too much.

It used to happen on my last 405 quite regularly with no effect on the running, one minute it would be on then the next it would go out again for no apparent reason. Sometimes it was linked to bumps in the road other times accelleration or deccelleration would trigger it. I have read somewhere that the sensors can be too sensitive. However it was easily solved on mine by a new fuel filter and cleaning the filter housing.

As far as I know water can be introduced to the fuel in many ways, most of them concerning refining and storage.

Wait until someone with the 605 handbook confirms, as I may be totally wrong, (If I am I appologise for the headache)

pug_owner2002 · Post by **pug_owner2002** » 19 Sep 2006, 22:20

Just looking in the 306 handbook and the lamp that you describe does sound like the "water in fuel filter warning light".
I seem to remember this coming on in a friends 306 and once the fuel filter was changed the light didn't come on again.
Don't know what would make the temp gauge jump around though.

Adstar · Post by **Adstar** » 20 Sep 2006, 10:07

Thanks for the confirmation. At least now I know what it is. All I need to know now is HOW it can happen?! (Although I have stopped worrying quite so much!)

I am still interested in anyone's suggestion with regard to the temperature gauge and its over active movements! I just want to know that the two things aren't related, and that i should not be expecting any impending doom!

The only time I have evr seen any activity on the temp guage like this, was on my MR2. It has a VERY air sensitive cooled system and that sort of movement teneded to be the fore warning of an impending over heat due to airlocks or air bubbles in the system.

Are peugeot deisels (specifically the 2.1) effected in this way? As you can appreciate, there is not really any documentation readily available about this car so I am hoping that someone has some useful knowledge they are able and willing to share.

Post by **CitroJim** » 20 Sep 2006, 19:07

In my experience the Water in Diesel warning lamp is a right pain. It cries wolf so often it's just not true. It only needs the tiniest bubble of water in the filter bowl and on it goes. Every Pug abd Cit diesel I have had has done it.

I find that the temperature gauge on my Xantia makes many excursions, especially when it is working hard towing or during stop-start runnig through towns after a good fast run before arriving at said town. I notice this effect especially in Milton Keynes driving fast between roundabouts, slowing or stopping and then taking off at a pace for the next.

As long as ithe temperature does not go further than the fan cut-in point and then rapidly falls there is nothing much to worry about. I take your point about the air bubbles though and I'd be very tempted to give the system a good bleed.

Back to the light, If it looks more like a little radiator, it could be your low coolant warning lamp telling porkies. Again, a pretty common problem, especially on a 205 which uses a reed relay operated by a magnet floating in a tube to sense a fall in coolant level.

Adstar · Post by **Adstar** » 21 Sep 2006, 13:06

Thanks Jim. I Have stopped worrying a little now. I replace the fuel filter fairly regularly as I am naughty and run a mix of vegetable oil in the fuel! I will keep a closer eye on the coolant levels. I have been sat in traffic during the hot weather so I should have been more observant.

But It wasn't a radiator on the light, so the water/fuel warning seems like the culprit.

Now all I have to worry about is the intermittantly slipping clutch!

Thanks again.