Clio 182 Engine Temp Gauge Going Up & Down

[Tom163]

Hi all,

The engine temp gauge in my 182 is at the minute really random! It heats up and never goes any higher than half way which is perfect but at random times and sometimes under acceleration the needle will drop noticeably and then return to half way and so on.....

I am going to bleed the cooling system tomorrow but has anyone else got any other suggestions?

Thanks
Tom

 

[Ol’ Tarby]

Possibly duff thermostat, and/or the temp sensor on the thermostat housing mate

 

[MicKPM]

That's text book air in the system/coolant system fault - bleed it and check for leaks

 

[Dan519]

I'd say thermostat gubbed.

 

[Tom163]

Hi guys, I have just bled the system with the following method:

Expansion tank cap off
start the engine with heaters on full hot going into the cabin etc
Undid the bleed screw slowly until a steady stream of coolant came out then tightened it up
Let the engine warm up and then did the bleed screw again
Once the engine was as hot as it wanted to go I switched the engine off and put the cap back on the tank.

Going to go have a drive see if thats made any difference. I also noted the temp sensor on the thermo housing had a cable tie on it so thats a big strange and are are marks on the expansion tank walls looks like gunk stuff....is that someone putting red coolant in without taking the green out properly?

Thanks

 

[MicKPM]

Well that's wrong to start with then.

 

[Tom163]

Which part mate? I went on a long drive and it didn't go up and down very much at all but it did between the half way and the mark just below, had to stare at it too see though.

Also did notice it fluttering a little when the engine was warming up so sounds more and more like the sensor surely?

 

[MicKPM]

The entire bleed process was wrong. You should never open a bleed point with the engine running.

Open all bleed points (if more than one)
Remove cap from coolant reservoir
Ensure car is on a flat/levels surface
Fill reservoir slowly until air free flow is observed from bleed point.
Replace bleed point bolt and fill to *just* over MAX point.
Replace reservoir cap.
Start engine and raise rev's to constant engine speed of 2k- 3k rpm until normal temp has been achieved and stat has opened.

**During the running up process you want to make sure the heater temp output doesn't go hot to cold then back to hot and also make sure the temp needle doesn't jump up and down**

Switch off and allow engine to cool
Adjust coolant level accordingly and replace cap.

 

[Tom163]

Wow I always thought bleeding was done with the engine on so the coolant flows round the system :/ how many bleed points are there on the F4R engines mate?

I really appreciate that advice will give it another go tomorrow.

Thanks

 

[MicKPM]

One on the 172/182 on the side of the stat housing. Sometimes, if there's a stubborn airlock you have to remove the coolant temp sensor but that's not normally an issue.

The cable tie around the sensor btw is normal and nearly all 182's have this.

 

[Tom163]

Thank you mate! will have a go this morning.

 

[incy-spider]

Failing all that, use a vacuum type machine, suck all air out of system until coolant pipes collapse, set machine to fill and let engine suck as much as it needs in, run up engine check when cool. Have also had temp sensors cause that fault when they are on there way out.

 

[MicKPM]

Temp sensor is another possible but I'd still want to know the coolant system has been correctly bled.

A thermostat (when faulty) won't normally cause a rapid spike on the temp gauge needle (it will normally be a slow falling movement).

 

[Toms_clio]

My old rb used to do this. Looked like a boost gauge going up and down lol. It fixed it's self tho haha

 

[Toms_clio]

My old rb used to do this. Looked like a boost gauge going up and down lol. It fixed it's self tho haha

 

[Sam_K]

Had this on mine, changed thermostat, cts and coolant, all fixed

 

[Tom163]

Thanks guys,

Definitely no air in the system now after following Micks guide thoroughly....still is going up and down but only a little.

It moves gradually between the exact half way mark when in traffic etc and it sometimes goes down to the mark just below when driving.... I have marked the picture how much it moves.

Thanks

 

[MicKPM]

If its bang on half way when stood in traffic and then slowly falls to the second mark when driving again (and doesn't move again until traffic) then that's normal.

 

[Amos91]

If its bang on half way when stood in traffic and then slowly falls to the second mark when driving again (and doesn't move again until traffic) then that's normal.

Is it really? Mine did this so I got the thermostat changed, now it rises to half way and does not budge no matter how its driven.

 

[MicKPM]

Yeah its pretty normal and depends greatly on the thermostat in there so as long as it's not up and down like a yo yo and the coolant temp isn't allowed to drop below 83°c then the thermostat is just regulating temp.

That gauge is also inaccurate and when it's dead central the coolant temp can be anything from 89°c to 110°c by which time the fan should've cut in.

Yes a new genuine stat will probably hold it better as his old one may be leaking a smidge but unless the temp gauge is dancing everywhere when cruising normally I wouldn't worry

 

[Tom163]

Thats great to know! I will eventually get the thermostat done as I want a proper coolant flush done to get rid of the old mixed bits.

Mick again mate you've been a massive help and thanks everyone else too!

 

[klm182]

Hi all,

The engine temp gauge in my 182 is at the minute really random! It heats up and never goes any higher than half way which is perfect but at random times and sometimes under acceleration the needle will drop noticeably and then return to half way and so on.....

I am going to bleed the cooling system tomorrow but has anyone else got any other suggestions?

Thanks
Tom

my did the same few weeks ago, got a new thermostat,and bleed the system ... since then its been fine..

 

[Gandi69]

Not sure if its been mentioned make sure you buy a genuine thermostat seal, third party ones are crap and leak after a few months which will leak and lose coolant, causing it to evaporate away which is hard to trace sometimes

 

[Tom163]

Sweet thanks guys, just fitted my new genuine Coolant Temp Sensor and seems alot better now....stays just under half way.

 

[incy-spider]

Told ya!