My temp gauge is dead, doesnt move of the bottom needle. Im assuming the thermostat is dead after a brief read through the common faults.

1) should I just assume that its dead and go and replace the full housing?

2) do I need to investigate anything else 1st?

3) will i kill my car driving 35 mls down the mway with a dead thermostat?

the thermostat is just a mechanical device which regulates the amount of water that can flow through the radiator, so it has no affect on the temp gauge.. it's more likely to be the coolant temp sensor on the housing, either that or a wiring problem

Id check the wiring to the sensor first very common for this to come loose or be a bit corroded disconnect the wiring and reseat it a couple of times and see if that has any effect, if it doesnt take the wiring off and clean up the spade type connector with a bit of emery board of similiar and reseat again and test it. If this doesnt work it could be either sensor or guage, but wiring would be my first bet.

I will check the wiring but should I need to replace the sensor looking on Butts

TS2 - 6U0819501 - Temperature Sensor (Inlet Manifold) - £20.99

Is this the right part? Is it easy to fit? I recently followed Haynes instructions to adjust my throttle cable the other day so I am feeling confident about tinkering.

no, that's the IAT sensor, that measures the temperature of the air going to the engine for the injection system....

what type of engine do you have?? mpi or spi?

your temp sensor will either be 6U0 919 501B or 6U0 919 501A depending on which engine you have.

on one type it's on the bottom of the thermostat housing and on the other type it's on the top

1.3 mpi

I have no idea where I got that code from, its nowt like the one I meant to write down,

butts have

6U0 919 501 Temp Sensor (inlet manifold)

6U0 919 501a Temp Transmitter

6U0 919 501b Temp Transmitter switch 4 pin

Worth checking that there is no response from the gauge when left running stationary....long enough for the fan to cut in.

If the thermostat has failed open - the gauge may take a long time to move and may hardly move (if at all) when driving.

Same symptom on mine when I first got the car. Was the coolant temp sensor, that's the 4 pin one by the thermostat. Cost

Forgot to mention, I tested the gauge was ok first. Haynes manual 3.6/11 there's a explanation of how, quite easy.

Same problem happened to mine. I opened up the housing and checked the thermostat. turns out the plastic clip and broken so the gauge werent reading anything. If its not the sensor, then try that but the coolant has to be drained

The gauge moves slightly when hot but i havent had time to do the daignostics mentioned in the haynes manual. As it moves I am assuming the gauge isnt dead. Trying to get this part has been problematic, waiting now on the dealer near work.

I am still going for the sensor up top (1.3 mpi push fit one) it recomends draining the coolant level or using a plug, if i swap in and out then I shouldnt need to drain should i?

Right help needed.

Just got what I thought was the replacement sensor from a dealer, read the Haynes and pulled the sensor (it gives the option to drain the coolant or plug the aperature, I opted not to drain the coolant) I pulled the sensor and it gushed abit, the replacement sensor doesnt fit. (looks the same from on top, blue ring, but the sensor in there now has a black chisel shaped end, this replacement has a metal cyclinder shaped end)

I have done it all back up as before with the old sensor, as there was a loss of coolant do I need to take any precautions or will it take it from the reservoir?

Im about to do Liverpool - Manchester, dont want to kill the car.

dont move the car till you have filled the coolant to the propper level

If it's any help here's what I can say about when I changed mine, from memory at least. The car is a '97 1.3mpi

Old one: chisel shaped plastic end, O ring captive, yellow collar

New one: Round flat metal end, separate O ring, yellow dot.

To change it, this is what I did. First of all I unclipped it and yanked it out, got covered in hot coolant, and put it back sharpish. I went in swearing at my stupidity and changed my shirt while the engine cooled some more. Second attempt, the engine now completely cool and for good measure depressurised by slackening the filler cap. Put a rag around it but this time there was virtually no spillage anyway. Put the new one in firstly placing the new O ring on it. Topped up any lost coolant (mainly due the first attempt) in the filler tank and screwed the cap down. Gauge now fine.

Couple of thoughts for you, sorry if any seems obvious but best mentioned just in case. Is blue the right colour code. Mine is yellow, maybe it's wrong but someone here can confirm that no doubt. Is there an old O ring still in the orifice, hence the new one won't fit. Does your heater get very warm quickly. If so should think the thermostat is shut when cold as it should be. If you want it I can probably find the part box and get the suppliers name and part no. I think they're based in Andover Hants. They have a web site. Hope that helps if only a bit.

I consulted skoda about the sensor, and they said that it was the right one (took photos of the old one, both have blue collars) i just needed a seal over the end, swapped them over, coolant dropped minimally so I didnt bother topping up (litterally 1 cm from the max line)

The new sensor hasnt cured the problem, the gauge does move slightly but only starts to move abit when stationary (ie getting very hot). I chased as much of the wiring as I could see but no breaks, corrosion or bad connections.

My only though now is the gauge itself, looking at how that all comes apart I am thinking with level of noviceness I will take it in and try and blag it with the dealer, have it since sept and has a warranty on it.

Sounding more like it could be the gauge then, bit of pain to get to I think. Could be blue or yellow collars are not critcal, anyway got to go the the local dealer later for some gaskets and I'll enquire to check I've got the right one (and what the difference is). If one of the mechanics is about I'll see what he reckons, let you know if there's anything to say.

Hope this isn't too daft a suggestion, but it's not that the thermostat's jammed wide open so that the engine's never actually warming up? :confused: I think this would mean you wouldn't get any hot air through the vents, but other than that I can't think of any other way of telling which doesn't involve a thermometer or possibly a multimeter...

plenty of hot air still, although not as much as usual.

Booked in tomorrow, will let you know how it gets on.

I am also waiting for the KLF to come back

plenty of hot air still, although not as much as usual.

Could be a clue to the problem perhaps (thermostat?) if the heater is not as hot as usual. One thing I like about the Felicia is that the heater gets warm fast, even before the gauge has moved much. Handy for me because I often have to be at work at some godawful early hours, so quick demisting is a bonus. So maybe you'd still get a reasonable amount of heat in the cabin even if the thermostat is open, but only a guess, not had a thermostat problem myself (yet). Anyway, if the dealer's going to sort it so much the better.

BTW I asked about the colour of the sensors and they were none the wiser what the difference was. There was a 1.3 in the workshop and it had a blue one. The parts man thought either was ok. Seems to work fine.

plenty of hot air still, although not as much as usual.

Booked in tomorrow, will let you know how it gets on.

I'd be interested to find out what the garage says - it does sound like a stuck-open thermostat to me, I must admit...

I am also waiting for the KLF to come back

:woohoo:

Quite a common problem on the later 1.3 a plastic part fails in the thermostat housing causing the failure of themostat. To change on the later models its the housing with thermostat complete and is one unit there is no option of just changing the thermostat.

Been down this route on my old Felicia - changed sensor - no joy then changed complete housing and all was solved. when the old unit was removed it was apparant by the bits loose in the housing.

I removed my housing without draining then topped up when job was completed with correct VAG antifreeze

John

would this cause it to run slightly rough is the sensor was reporting a cold engine to the ecu?

would this cause it to run slightly rough is the sensor was reporting a cold engine to the ecu?

I'm certainly no expert but when I changed mine a mechanic friend told me this. If the CTS fails and reports a cool engine when it's actually hot, it would run rough because the mixture would be wrong (too rich presumably). Logically that seems to make sense but someone please say if it's wrong. Mind you if the thermostat has failed, then the coolant is too cool anyway. If you've already changed the sensor with no change, I would rule it out unless it only ran rough on the old sensor, in which case you might have more than one fault. Be interesting to hear what the dealer says.