hi, recently i been having problems with my felicia temperature. its been showing erratic temperature readings, showing hot temp when the engine is cold or showing nothing at all. now i bought a new coolant sensor (with the yellow ring) as the old one, and i fitted it and its now showing temperature as the one in the picture when the engine is hot, is this normal or the engine should stay at the middle mark only? i want to add that i also did try another temperature gauge and the readings remained the same and also the thermostat is brand new.

Mine normally hovers on the 90 degree line unless in traffic, but looking at your profile it says you are from Malta which wouldn't surprise me if it normally ran a bit hotter than mine with your climate.

... looking at your profile it says you are from Malta which wouldn't surprise me if it normally ran a bit hotter than mine with your climate.

A cooling system in good order self-regulates the coolant temperature at 85-90 C regardless of geographical location, load or outside temperature. The thermostat, the radiator fan switch and the radiator fan do that. For countries with warm climate Skoda fitted thermostats and radiator fan switches with different opening temperature to prevent the radiator fan running too often.

Edited 7 March, 201610 yr by RicardoM

So most likely OP has incorrect temperature band sensor or gauge error? What else could cause.it to run at consistent slightly too hot temp?

Trapped air below sensor or too low on coolant. It happens most of the time after opening the cooling circuit.

Thanks for the replies but somehow it worked by just connecting the sensor in reverse it is now showing good temp. I cant understand how this sensor works in reverse lol

Thanks for the replies but somehow it worked by just connecting the sensor in reverse it is now showing good temp. I cant understand how this sensor works in reverse lol

It is impossible to connect the sensor 'somehow' in reverse because it is keyed. How about the truth?

Yeah i know its keyed but i did put it in the other direction and it worked

This is bizarre i know but thats the truth. When it was keyed it wasnt showing good temperature

Can't you get it? You can't physically insert the connector "in the other direction". Moreover, let's say you use a sledgehammer :strong: and you insert it "in the other direction". That woud be worse. Why? Because the other thermistor inside the sensor (see photo) has twice the resistance of its pair. Instead of showing 100 C as you complained, it would show less than 70 C.

 

These are physical facts. You know... physics... as in "a 110 story skyscraper can't turn into dust and free fall in under 10 seconds" physics. So I am amazed that you prefer spreading fake information instead of admitting the trapped air eventually went away after more driving. You have the bad habit of not doing anything you are told here or not admitting you got good advice because in your mind that would mean you have poor knowledge on the subject. I have reviewed all your topics and there is a pattern in your behavior. In other words, helping you proved every time to be a waste of time because in the end you came up with 'personal solutions' or blatant lies. Grow up.

I will post a video to show you

i cant find a way to upload it... first of all this is not a problem with coolant level, thermostat or air trapped in air system, because i bled the air system, filled the cooling system corrrectly and the thermostat is almost brand new and opening corrrectly.

 

i driven the car for about 10 minutes only, and switched off for an hour. when i fitted the gauge in the correct position, the gauge showed that the temperature was still at 90 degrees !! usually my car after an hour cools sufficiently so that the gauge shows below 70. i checked the hose to the raddiattor, it wasntt even warm. and witth engine running, the thermostat wasnt even open (i checked for flow of coolant from expansion tank),when i fitted it the other way it showed below 70 when still was switched off, and when i switched it on, after 2 minutes the engine was to 80 ish temperatures again.

 

see what i mean ?

Is it possible that an engine warm up to 85 degrees in just 3 minutes ??

Allow me to reuse this topic...

I read around the forum a bit and figured that quite a few topics are out there about the same thing: Temp gauge reading 70 or thereabouts. 

So , this is my case as well. Noticed that as i bought the car on Friday.

 - this is pretty low mileage car 60000km, so i expect most things original factory item. also owner was not a tuning enthusiast, rather a Grandpa...

- it was used very little over the last few years, so i'd not be surprised if thermostat could be stuck

- that said, i did not notice warm radiator hose after firing it up and i did notice getting heating out of the heater fairly quickly. So my fist impression is that thermostat is OK.

(I'll check that again probably with coolant temp sensor resistances)

- that engine temps are OK is further supported by that cooling fan switched on after we turned to a petrol station off the highway and it switched off soon. Does not look like a stuck thermostat, but again, i'll check further.

 

So, my main question is pure curiosity: If temp sensors are different for the selection of dashboards, what is the difference between them?

Like what's the difference between blue / yellow / etc sensors? Only the thermoresistance inside? 

and if someone managed to pop in the wrong sensor, how would that alter the ECU's operation? Would the car still go pretty well, or would it cause too hot / very low temp modes and ECU would send ignition, injection commands all over the place? 

 

That is my question basically. Otherwise i'll stick to what i read so far, measuring the resistance between the sensor pins, checking warmup / fan-on times.

 

Ah! I do remember seeing in one of the posts some reference to a felicia workshop manual. Today is pretty hard getting the like off the internet without much suffering / subscription, marketing, etc... anyone has a working link to a pdf??

 

It's actually a huge fan driving such a car. So outdated (my version is the bottom edition from 1997), you'd expect Hasselhoff to pop put of the dashboard singing Ughachaka or something!  It looks as old fashioned inside as my 1988 Saab... Having said that, it has an engine that's comparable in modernity with my Mother's 2007 suzuki swift. It's quite cool. 

On 02/05/2022 at 13:21, hzoltaan said:

Like what's the difference between blue / yellow / etc sensors? Only the thermoresistance inside? 

Yes. Remember, there are two thermistors inside. One for the gauge and one for the ECU.

 

On 02/05/2022 at 13:21, hzoltaan said:

if someone managed to pop in the wrong sensor, how would that alter the ECU's operation?

Wrong coolant temperature signal, inefficient operation of the engine. I mean, not to the point the pistons will fly out the bonnet, but possible rough idle, higher consumption, etc.

Managed to look inside the beast a bit deeper: 

Engine code: 781.136M, sensor has yellow ring.

 

Tested the whole thing:

Makes me pretty sure that the temp sensor is faulty. Somewhere i saw a temp / resistance chart but i did not click enough the retrieve it now. Still, I remember they were not equal. Mine are suspiciously close to each other in value (like 310 and 290 ohm when fan turned on)

 

Startup: outside is about 15Celsius, both resistors are at 3Kohm

8-9 minutes idle: gauge shows under 70, thermostate opens, top rad hose gets warm, both resistors are at 0.3Kohm

15 minutes idle: fan cuts in, gauge shows 85-ish, boths resistors are about 0.2Kohm

 

So, given that at 90 (I guess thermostat opens at 85 and fan kicks in around 97?) theyshould be 125 / 250 ohms, getting higher read explains to me why my gauge shows less. And probably the ECU was feeding a bit too rich mixture too thinking it was ticking at 70ish all the time? 

 

FEBI Bilstein is a pretty decent manufacturer, right? 

Lovely part prices. I'm rediscovering the awesomeness of owning a simple and yet not too old but very popular car. Parts are abundant and cheap. Try the same with a Saab 900!  

 

 

and now the best part... 

For my car 68horses MPI Felbi catalogue says that i need the blue sensor:

https://partsfinder.bilsteingroup.com/en/article/febi/39142?make=Škoda&model=Felicia+Combi+1995+-+2001&vehicle=1.3+MPI+-+50+kW+%2F+68+hp

Everywhere on the forum i read yellow sensor. 😛 Damn! 

 

Eventually i was sent home from the part shop. X) The Man (a good friend of mine) said he will not sell me any sensors whatsoever if i do not have the proper number. So I did my new trick of sucking out the coolant with a small 12V pump out of the expansion tank, popped the sensor out and ordered a new one. 

 

Tomorrow I should have it and will compare resistance values just for the fun of it.

My car ('97 1.3 MPI, 136M engine) had this part in it: 357919501A

99%  that it's original part as the datestamp on it is 97 January.

 

5 hours ago, hzoltaan said:

My car ('97 1.3 MPI, 136M engine) had this part in it: 357919501A

 

 

 

There are many options, here is an Example but don't trust the cheap ones.

 

On 02/05/2022 at 13:21, hzoltaan said:

and if someone managed to pop in the wrong sensor, how would that alter the ECU's operation? Would the car still go pretty well, or would it cause too hot / very low temp modes and ECU would send ignition, injection commands all over the place? 

 

You can not go ''too much wrong" but it's easy to understand when you are in trouble, for example here that we have hot climate you can easy see the needle goes above the 95 'C mark and if passes that you have to stop and check some things.

It's not normal to drive with temperature around 100 'C, soon or later you will pay the price for this.

 

Thanks Fylaktos! 

 The parts shop ordered me a Delphi part, so we'll see. Just for kicks i'll do the same test with the new part as i described above and we'll see the difference. 

 

I wonder what the ECU thought what temperature the engine was when the sender gave it 300ohm. (I measured 300ohm when the fan turned on on the pins that feed the ECU) 

Did the ECU think it was around 70degrees? And I wonder if the car will now run better with the new (and correct) sensor. I had a wee-bit rough idle or more like a barely noticeable oscillation up and down, plus i smelt a bit of petrol around the car. We'll see if that's gone. 

24 minutes ago, hzoltaan said:

I wonder what the ECU thought what temperature the engine was when the sender gave it 300ohm.

 

I had in the past an adaptor before the thermostat sensor and a gauge connected so i could read the coolant temperature before reach the thermostat.

 

 

 

This is my centre console.

 

 

So, new sensor is in, and i did the same test: 

Right out of the box the two resistances did not equal. So the original sensor was definitely broken. 

let's call the gauge's resistor R1, the ECUs R2.

 

Startup: outside is about 20Celsius, R1 = 1.5k, R2 = 3.1k

8-9 minutes idle: gauge shows 85ish, thermostate opens, top rad hose gets warm, R1 = 120ohm, R2 = 290ohm

15 minutes idle: fan cuts in, gauge shows 110-ish, R1 = 80ohm, R2 = 170ohm

 

Engine does not sound any different, and it still osciallates a bit. I guess something else is the culprit.

The exhaust on the other hand does not smell like petrol that much, so i guess injection/ignition is closer to optimum. 

 

We'll see on the road, i have not driven yet. 

 

Thanks for all the comments!

 

On 07/03/2016 at 20:43, RicardoM said:

For countries with warm climate Skoda fitted thermostats and radiator fan switches with different opening temperature to prevent the radiator fan running too often.

 

I am living in a Hot climate country and the "too often" (especially in traffic) is desirable, so why Skoda must "prevent" it?

20 hours ago, D.FYLAKTOS said:

I am living in a Hot climate country and the "too often" (especially in traffic) is desirable, so why Skoda must "prevent" it?

You will have to find the answer by yourself.

Edited 6 May, 20224 yr by RicardoM

Today all the Skodians learn a lesson: ''when you live in a country with hot climate the radiator fan of your car must don't run too often''

Any questions? No, OK then.

 

22 hours ago, D.FYLAKTOS said:

Today all the Skodians learn a lesson

The interpretation of my initial statement is only coming from YOUR level of understanding. That does not make you the spoke person of "all Skodians". It is just you and your level of knowledge.

I would like also to add that I prefer you to stop interacting with me on any level. I really don't care what you think you know about cars or how big of a tragedy is any minute issue.