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Hi, interesting you mention the coolant. It hasn't dropped enough to raise a sensor, but it has dropped from just over full to just above the bottom line in 8 months. I'm not sure if that's normal for a car of this size though. I do motorway miles almost every day however and it seems to be happening even after giving it a good 'boot' daily.
It's a 1.4 tsi petrol.
Edited by F22 on 06/05/2022 at 05:19
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The coolant shouldn't drop, that's where I would be trying to focus the garage's attention. It might be something unrelated and simple like a bad hose clip or something a bit more serious like the head gasket. I don't know how they test for that these days, in the past garages could stick a sensor up the exhaust to analyse the gases.
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I don't know how they test for that these days, in the past garages could stick a sensor up the exhaust to analyse the gases.
Not heard of that. Testing for exhaust gases (and/or oil) in the coolant/radiator head space, and/or coolant in the oil, is what's usually discussed, though with a one-way leak this wouldn't show anything. Pressure testing the cooling system is also a thing.
While I suppose testing for coolant in the exhaust gases is a technical possibility (by gas chromatography looking for an ethylene glycol signal, for example, or perhaps adding some additional marker (dye?) to the cooling system) I doubt garages have the capability.
If its a HG leak I'm puzzled by the OP's mention of the clutch position affecting it though.
I was also a bit puzzled by the OP's mention of "Whitt's end".
In my doddering geekiness I thought of whitworth spanners, (which havn't been relevant for a long time) but it apparently has another meaning these days.
www.urbandictionary.com/define.php?term=whitt
Edited by edlithgow on 07/05/2022 at 02:44
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I was also a bit puzzled by the OP's mention of "Whitt's end".
I take it to mean got fed up with it.
I`m not so sure its a problem as such because you can buy tuned exhausts to make that sound, I have heard them many a time and a chap not far from me had his exhaust on a VW Passat replaced that sounds exactly the same, even a local Mustang has the same sound, some as I said do not like it.
I prefer that baubling sound to straight through exhausts, but some don`t...
the loss of coolant isn't that unusual on some motors as max to min after a month or so (a reason why your supposed to check levels) just my thoughts anyway!
some don`t admit to modified replacement exhausts for insurance reasons so the main dealer may not know? and too costly to put back to standard???
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You're correct - its a southern expression, Sorry.
It is a possibly, a few people have Said it sounds like a boy racers car! Embarrassing when you're doing the school run!
A friend did suggest to me it could be the baffles? However I would assume that if it was the sound would be 24/7, not just after long journeys / idling.
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You're correct - its a southern expression, Sorry.
It is a possibly, a few people have Said it sounds like a boy racers car! Embarrassing when you're doing the school run!
A friend did suggest to me it could be the baffles? However I would assume that if it was the sound would be 24/7, not just after long journeys / idling.
It could be the baffles as they control the sound, idea of baffles is to cancel the engine sounds so the engine sounds quiet, not noisy at the rear, size and shape of the exhaust make a difference to the sound so its possible someone had the rear silencer changed/whole exhaust to give that sound, that sound can be altered according to design
not all boy racers use them as not everyone likes that sound
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Ha, yes 'whits end' means fed up - its a southern expression.
As I say, the moment the car is put into gear, even if not moving, the sound stops I believe the service dept are currently in discussion with their HQ about what to do - I was supposed to have it back yesterday but they phoned and asked if I could keep the replacement car for a few more days as their still waiting for 'advice'. I wonder if just changing the exhaust system would fix it, may well suggest that when they contact me again, but they did say everything is how it should be but there is a lot of fluid coming from the exhaust, more so than they've seen on other tiguans and they've 'collected' it to test.
The engineer I spoke with said there is a possibility that the engines getting too hot at times and so as its water cooled its using and dumping the water, but I haven't had any sensors go off and no engine management lights flash up. Just people in the street inform me that my cars making an awful noise!
Edited by F22 on 07/05/2022 at 08:07
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The engineer I spoke with said there is a possibility that the engines getting too hot at times and so as its water cooled its using and dumping the water, but I haven't had any sensors go off and no engine management lights flash up.
Was this an engineer or the toilet cleaner?
Engines are designed to get hot, its what they do. Modern cooling systems are not only sealed but the expansion is part of this pressurised sealed system as well, even in extreme situations coolant will not be "dumped".
But to suggest that the water is being dumped into the exhaust is beyond belief. All engines create some water as a by product of combustion, its what we see on cold mornings. But for an engine to dump water into the exhaust means one thing only, an head gasket failure.
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Thank you for this, i know nothing about cars and feel like I'm being spun a Web. I feel like I've thrown 19k at a car and it was a huge mistake, but VW won't 'buy back' due to faults and the only thing I can do is just keep taking it back whilst it's under warranty.
Do you have any advice on what I should be asking/ pushing for test wise?
Edited by F22 on 07/05/2022 at 09:06
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Do you have any advice on what I should be asking/ pushing for test wise?
As above (in bold), pressure test the cooling system. IF its got a significant leak into the exhaust it'll slowly loose pressure.
However, if its a very slow leak this procedure may not be sensitive enough to pick it up.
Also as above, they should test for exhaust gases in the rad, oil in coolant, coolant in oil, though a one-way leak could still exist without these.
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"Not heard of that. Testing for exhaust gases (and/or oil) in the coolant/radiator head space, and/or coolant in the oil, is what's usually discussed, though with a one-way leak this wouldn't show anything."
You are probably right and I'm getting confused. When I had a VW back in the early 90's with suspected HGF they stuck something in the exhaust and also some sensor in the expansion tank. The two may have been unrelated.
Edited by Xileno on 07/05/2022 at 09:09
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"wits' end" - the limit of one's sanity or mental capacity : the point of desperation
wits' end - Wiktionary
Used in both Britain and USA but an "old-fashioned" expression you don't hear much
History. The phrase originated in the King James Version of the Holy Bible in Psalms 107: 27. “They reel to and fro, and stagger like a drunken man, and are at their wits' end.”
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"wits' end" - the limit of one's sanity or mental capacity : the point of desperation
wits' end - Wiktionary
Used in both Britain and USA but an "old-fashioned" expression you don't hear much
History. The phrase originated in the King James Version of the Holy Bible in Psalms 107: 27. “They reel to and fro, and stagger like a drunken man, and are at their wits' end.”
Yeh, but "whitt" apparently means something like "hunk". (see Urban Dictionary link above)
"Whitts end""?...I couldnt say.
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Typo. Means the same thing as above, to be in despair. Regardless of how you spell it - where I'm from in Kent, it makes no difference - it still means 'had enough'.
Anyway, I thought this group was about cars?
Edited by F22 on 07/05/2022 at 18:52
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It is, although a bit of harmless thread drift is allowed.
However, to get back to the car I would be more concerned about the coolant loss than the exhaust noise. The two may be related. The garage need to check for HGF. As it's still under warranty and they've accepted that something's not right, then I would give them one more attempt to resolve it and then push for not a refund (because I don't think that will happen) but an exchange. If you still can't get any satisfaction then I would get in touch with a solicitor that gives a free appointment to see what options may be available to you. I might also be thinking of an independent vehicle inspection but you would have to pay for that yourself and you may/may not be able to claim it back.
I may be wrong but I would be concerned that the garage are just going to drag this one out until the warranty expires.
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they do a combustion leak detector for the coolant that tells if a head gasket has blown, some use mot tester exhaust checker to sense any. but may not detect a water jacket head crack into exhaust though, and if it has a water cooled exhaust (not certain if that is diesel only) could be a leak from exhaust manifold
if no oil in water, or water in the oil, would possibly look at head crack, but not knowing amount of coolant it takes from min to max could be normal over timespan mentioned?
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some use mot tester exhaust checker to sense any.
Sense any what?
That would be consistent with what someone was saying above, but I'm wondering what signal they are looking for.
I wouldn't expect MOT emissions testing kit to pick up, say, ethylene glycol, though I don't know for a fact that it can't.
I THINK most coolants contain flourescent dye, but I dunno if much of it would pass through the combustion chamber unchanged. IF it did you MIGHT be able to pick it up with a UV light in the dark.
Probably uninterpretable without a lot of comparison of different cars, which no one is going to get into if it isn't already a recognised technique
Edited by edlithgow on 08/05/2022 at 02:57
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some use mot tester exhaust checker to sense any.
Sense any what?
That would be consistent with what someone was saying above, but I'm wondering what signal they are looking for.
I wouldn't expect MOT emissions testing kit to pick up, say, ethylene glycol, though I don't know for a fact that it can't.
I THINK most coolants contain flourescent dye, but I dunno if much of it would pass through the combustion chamber unchanged. IF it did you MIGHT be able to pick it up with a UV light in the dark.
Probably uninterpretable without a lot of comparison of different cars, which no one is going to get into if it isn't already a recognised technique
Exhaust, analyser checks expansion tank for combustion gases
But it is possible the leak if any?, could be one way or directly into exhaust port which means it wont show up on that test.
Its also possible and have been behind many motors going uphill that the Cat has left a lot of water in the silencer /s which pours out going uphill, as the water loss occured over 8 months the water loss may be an acceptable amount, but not sure of top up amount between empty mark and full?
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some use mot tester exhaust checker to sense any.
Sense any what?
That would be consistent with what someone was saying above, but I'm wondering what signal they are looking for.
I wouldn't expect MOT emissions testing kit to pick up, say, ethylene glycol, though I don't know for a fact that it can't.
I THINK most coolants contain flourescent dye, but I dunno if much of it would pass through the combustion chamber unchanged. IF it did you MIGHT be able to pick it up with a UV light in the dark.
Probably uninterpretable without a lot of comparison of different cars, which no one is going to get into if it isn't already a recognised technique
Exhaust, analyser checks expansion tank for combustion gases
But it is possible the leak if any?, could be one way or directly into exhaust port which means it wont show up on that test.
Its also possible and have been behind many motors going uphill that the Cat has left a lot of water in the silencer /s which pours out going uphill, as the water loss occured over 8 months the water loss may be an acceptable amount, but not sure of top up amount between empty mark and full?
Ah OK. You mean they check header/radiator for CO/CO2 using the exhaust gas analyser, rather than using the chemical colour change kit.
Makes sense.
I thought you meant checking the actual exhaust, which someone mentioned being done above.
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some use mot tester exhaust checker to sense any.
Sense any what?
That would be consistent with what someone was saying above, but I'm wondering what signal they are looking for.
I wouldn't expect MOT emissions testing kit to pick up, say, ethylene glycol, though I don't know for a fact that it can't.
I THINK most coolants contain flourescent dye, but I dunno if much of it would pass through the combustion chamber unchanged. IF it did you MIGHT be able to pick it up with a UV light in the dark.
Probably uninterpretable without a lot of comparison of different cars, which no one is going to get into if it isn't already a recognised technique
Exhaust, analyser checks expansion tank for combustion gases
But it is possible the leak if any?, could be one way or directly into exhaust port which means it wont show up on that test.
Its also possible and have been behind many motors going uphill that the Cat has left a lot of water in the silencer /s which pours out going uphill, as the water loss occured over 8 months the water loss may be an acceptable amount, but not sure of top up amount between empty mark and full?
Ah OK. You mean they check header/radiator for CO/CO2 using the exhaust gas analyser, rather than using the chemical colour change kit, which is a consumable that would need to be bought, and isn't quantitative.
Makes sense.
I thought you meant checking the actual exhaust, which someone mentioned being done above.
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Heres a famously irritating American on coolant system leak detection.
www.youtube.com/watch?v=rDuGeQnMOzk
Dye for leak finding is probably commoner in the US.
Dunno how available in the UK, or, critically, whether it would get through to the exhaust pipe, but it might be worth a try.
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Heres a famously irritating American on coolant system leak detection.
He reminds me of the first Mechanic I ever worked under as an apprentice, similar voice and attitude
I have doubts they would use dye (for some reason not many use it? that I recall) I suspect but could be wrong, it would take a while to show up at rear of tailpipe if it does at all...
but would most likely pressure test for a while and if there is a drop in pressure would investigate from there, ie possible exhaust manifold strip down ...?
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