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All connections checked, no wet carpet inside, no wet patches on garage floor and pressure checked ok. Having searched the internet the only thing I can find is a report of similar problems being caused by a faulty thermostat, however the temperature gauge doesn't show any signs of overheating, anyone any thoughts?
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Could still be a leaky head gasket, you only tend to loose water if you push it hard. Put a container under the overflow pipe, if its collecting coolant that's probably what it will be. If the leak isn't to bad you can try leaving the filler cap loose, this prevents it pressurising and blowing the coolant out, but bear in mind that it will reduce the boiling point so don't thrash it.
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If the leak isn't to bad you can try leaving the filler cap loose, this prevents it pressurising and blowing the coolant out, but bear in mind that it will reduce the boiling point so don't thrash it.
Please don't do that. Cars have a sealed expansion tank for a reason. Even if it did not blow water out while you were driving it would with 100% certainty blow it out once you stopped as the residual heat from the engine transferred to the water.
Lift the bonnet and you could end up with serious scolds or worse.
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Cooling system temperature and pressure are directly related. As the temperature increases so does the pressure. As the temperature reduces so does the pressure. If you see a quick increase in pressure without an accompanying increase in temperature then it's a sure sign the head gasket has failed or there's a problem with the cylinder head.
When the engine is warm make sure that heat is being dissipated from the radiator. If it isn't check to make sure the radiator fins are in good condition and free of dust and dirt which would restrict air flow. Make sure the radiator is warm all over, and not just at the top. The top should be hotter than the bottom but not by much. Also check to make sure the heater blows hot. Anything wrong here may be why your engine is overheating.
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If you have satisfied yourself that none of the nasty things have happened, there must be a simple seepage somewhere. This will only happen when coolant is hot, so there should be a coloured stain where the water has evaporated. Have you looked everywhere?
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I would check the engine coolant temp sensor situated at the end of the cylinder head,above gearbox.It is not uncommon on these for coolant to leak internally and into the 2 pin plug and wiring,and eventually make its way up to the engine control unit.
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I agree with the above comment the wifes 207 vti had a simialr issue collant seaping from the temp sensor causing eratic starting
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I have driven a Citroen XM diesel with the filler cap loose for about 4 years without having to top the water up, if you screw the cap down and drive up the motorway it blows it all out when it gets hot. As long as you don't thrash it the water won't get hot enough to boil.
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I have driven a Citroen XM diesel with the filler cap loose for about 4 years without having to top the water up. As long as you don't thrash it the water won't get hot enough to boil.
Peter, I think this will be more true for a diesel than a petrol. And what about climbing a long hill?
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Thanks to all of you for your input, however we decided to take it to the local Peugeot dealer and last Tuesday they said the leak was a "seal adjacent to the oil pump" and the reason for the intermittent nature was "it would only leak when the engine got really hot". I must admit I was a bit sceptical about this but hey ho they are the experts. So yesterday my wife set off on her twice weekly journey to work (90 mile round trip). Before setting off on the return leg she checked the water and it was as it should be, whoopee she thought. However on her reurn to home the expansion bottle was empty. Left it to cool down and then refilled it with 2 pints of water. The car is going back to the main agent today, hopefully they'll fix it properly this time. Will keep you posted on this mystery.
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It's probably of no direct help, but I owned a 205 which had a coolant leak from a cracked housing under the engine. It didn't lose a lot of water, but its position was given away by a water stain on the garage floor. You have to look everywhere .....
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I have looked everywhere, even had it up on a ramp in a friends garage who also pressure tested it for me. There is no signs either on the floor or as far as I can see on the engine. When the expansion bottle is empty it still has a healthy pressure proved by the blow off when I begin, slowly, to unscrew the cap. This is why, rightly as it turned out, I was so sceptical about the "leaking seal" that the main agent claimed was at fault. Anyway it's back there now and hopefully they'll fix it this time. I'm still going for a faulty thermostat that was the cause of a similar problem posted on the RAC site. Having said that I still don't know where the water goes, a real Agatha Christie puzzle.
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The behaviour you reported earlier sounds as if the coolant is lost in bursts rather than slowly and steadily? To me that sounds like a pressure release, as one used to get from those spring-loaded radiator caps. That would fit with your not finding any puddles, but there must be visible evidence somewhere (staining). Two pints cannot be accounted for by your dealer failing to clear any airlocks?
Edited by Andrew-T on 15/08/2014 at 13:48
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Latest update. Main dealer has had the car all day and can't find anything wrong with it but would like to keep the car til tomorrow lunch time. Watch this space for further news about the mystery of the missing coolant!!!!!!!
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HGF.. is my guess. When it's warm and under load.. Happened on son's 1.- 106.
Water escaping via exhaust.
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As a cheap but risky fix, you could try torquing the head bolts. Mechanics don't like the idea as they are stretch bolts, but it might be worth a try?
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If they are stretch bolts there isn't a torque to retorque them to? They will be way beyond the torque setting used before the stretch is applied. Is the eqivalent of re-torquing to give them an extra x degrees? How many degrees is x?
(Interested in the answer as my MX5 appears slowly to lose oil into the coolant, which I attribute rightly or wrongly (more likely) to a pinhole somewhere.
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Latest update, car returned from garage yesterday with nothing done, they queried the fact that we put 2 pints of water in it last time it leaked, which I did, took the time and trouble to fill when cold using a pint measuring jug. I am more convinced that the coolant is being blown out of the pressure cap on the expansion bottle, so I've wrapped an old tea towel round the cap. If I'm right and there is coolant loss after my wife returns from work on Monday the towel will be wet. Now a case of wait and see.
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As above, i can't see how this amount of coolant can be vanishing without leaving a stain, have you jacked it up and had a proper poke nose underneath, thats where any stains should accumulate, trace it upwards.
Has anyone checked the sensor ElecDoc above mentioned.
Sniff test of coolant should rule OMG HGF in or out.
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I would still go for the head gasket, I have had so many go I am well aquianted with the symptoms.
Andrew - You may well be right, I have run diesels for so long I tend to forget there is an alternative!
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Bingo , wife has returned from work, bottle empty, towel soaking. We now know for sure that the coolant is being blown out of the expansion bottle. Taken back to main agent who has lent my wife a courtesy car while they investigate further. They're talking of a crack in one of the cylinders which is not uncommon on this engine. Now they tell us!!!!!!!!! I'm still not convinced it's not the thermostat sticking, another common problem with electronic thermostats. Anyway once again we wait with baited breath. Watch this space.
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We now know for sure that the coolant is being blown out of the expansion bottle. They're talking of a crack in one of the cylinders which is not uncommon on this engine.
Interesting. I would have thought a gasket failure is more likely than a cracked cylinder, but either way it doesn't sound like a cheap fix. Presumably the HG is letting cylinder gas into a waterway somewhere?
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A new pressure cap on the expansion bottle should do the trick. Its a spring loaded diaphragm and they can wear so they then do not hold the pressure and thus allow vpaour, hot water out of the system when hot
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Can't do any harm. But you still need to cure the source of the pressurising, or it will just blow the new cap at a higher pressure.
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Apologies for the delay in this post but the problem has now been sorted. It turns out that the temperature sensor was at fault, which in turn was not opening the electronic thermostat and hence the engine was overheating and blowing the water (in the form of steam) out of the expansion bottle. The only question left is why the temperature gauge didn't show this overheating. In fact it read lower than normal, 70deg against 90deg. Once again thank you to all who contributed, just as a matter of interest is this engine (1.4, 90bhp petrol) used in any other cars? If so be advised as I have been told that this is not an uncommon failure.
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.... the temperature sensor was at fault, which in turn was not opening the electronic thermostat and hence the engine was overheating and blowing the water (in the form of steam) out of the expansion bottle.
.... just as a matter of interest is this engine (1.4, 90bhp petrol) used in any other cars? If so be advised as I have been told that this is not an uncommon failure.
If all these reasons for failure are 'not uncommon', why did the garage suggest the more expensive ones first, I wonder?
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