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Think i have the same issue

It seems my Temp Gauge goes up to 90, then when on motorway etc goes down to around 75, then back up etc...

On the climate control doing the trick and selecting 51, it seems to get to 90c and stay there!

Am i right in thinking this is a sensor issue rather than thermostat ? If so are these easy to change?

Thannnnnks

Ti
 
Engine temp problems

Hi,
I was reading your post from last year. Did you ever get to the bottom of the problem? Mine has just started happening. I've replaced the CTS and was going to do the stat this weekend but would rather check out other fixes just in case.
Cheers
 
I was reading your post from last year. Did you ever get to the bottom of the problem? Mine has just started happening. I've replaced the CTS and was going to do the stat this weekend but would rather check out other fixes just in case.
Cheers
 
I was reading your post from last year. Did you ever get to the bottom of the problem? Mine has just started happening. I've replaced the CTS and was going to do the stat this weekend but would rather check out other fixes just in case.
Cheers

This is actually a current problem and a current post so welcome to the thread... I am replacing my cts again this weekend with a genuine one from Sere motors. I checked and it is highly likely that it is either the cheaper cts I put in or the actual wiring or dials. On this thread you will most likely find most checks and methods to help you but I've not as yet fixed it.
 
Hopefully sorted!

So this morning I fitted my genuine cts that I bought from Sere motors NI. and it Went well. To be lazy, I bought a funnel and I cut a cuff of a 2l coke bottle and I unplugged the negative connection on the battery (ensuring I knew my radio code) and unscrewed the intake pipe from the air filter housing (the pipe that contains the MAF sensor), unplugging the maf sensor lead before doing so; so that I could move it completely out of the way. I then unplugged the cts connection, took out the u clip that is on the sensor. I dropped a 2l bottle into the engine bay and inserted the funnel. I then inserted the cuff of the 2l bottle I cut up before, to bridge a gap and act as a splash guard as I knew it would miss otherwise and I also wasn't sure if it was going to gush out or trickle. I left the reservoir lid on to form a vacuum but also had a bit of spare coolant ready in case. I then slowly prised the sensor off. It caught all the coolant it was going to dispel (between 1-2l) and I could then fit the new sensor and put my coolant back in. However.... The climatronic got to 90 but my temp gauge didn't budge off 60. I decided to go on a 22 mile drive of dual carriageway normal roads and motorway and upon driving the dash gauge quickly and steadily reached 90 (I'd obviously preheated so not surprised) both gauges read 90 on the whole journey without stutter so maybe the dash gauge just needed to calibrate itself - fingers crossed anyway and I will be monitoring it. The climatronic gauge; having switched off and on again is slowly rising up whereas the dash gauge went straight back up to 90 which leads me to believe that a) digital and analogue cannot be compared accurately and b) when reading the temperature it will always have to climb back up the numbers to show an accurate figure, which I think would explain the variances between the two gauges when I turned off the car before when idling it to temperature and then setting off on the 22 mile trip. For anyone reading this who is looking at other options than to spend money on parts.... Spend the money... Buy a genuine cts and if that doesn't work, a thermostat and don't muck about like I did trying to guess game it. The guys on here are right and I was wrong. It's a bit of trial and error - cheers
 
That's because it has to be converted back to analogue. The signal from the temp sensor is analogue it then gets converted to digital for the ecu, the ecu then sends it out to the displays. The climate is digital so understands but your gauge isn't so has to be converted again. As with any process something gets lost. ( correct me if I'm wrong but that's how I understand it.)
 
That's because it has to be converted back to analogue. The signal from the temp sensor is analogue it then gets converted to digital for the ecu, the ecu then sends it out to the displays. The climate is digital so understands but your gauge isn't so has to be converted again. As with any process something gets lost. ( correct me if I'm wrong but that's how I understand it.)

No, the CTS as Two senders one for the ecu and one for the dash.
I'd think the climate would get the ecu signal too?
 
Well I'm probably going to plead ignorance after a week or two of checking. I'm happy for a slight variance so long as they both get to temp in a similar time frame. You heard it here first folks... Ignorance really is bliss! (I wish!)
 
Don't know if its because its 1 degrees out but my 2.5 mile journey in to work I monitored both gauges and the dash gauge got up before the climatronic and nearly got to 90, then as I slowed down into town and nearing work and parked up it drifted down to the 1/4 mark and stayed there. Is this a usual event in colder weather? I wouldn't say it moved down particularly suddenly; it was gradual. The climatronic on its way up dropped down a degree once or twice too which it has never done before but still rose relatively consistently? Some advice would be welcomed...
 
Obviously when the dash gauge rises it should get to 90 and stay firm there, no matter how cold it is that is the thermostats job to keep it at 90
 
Obviously when the dash gauge rises it should get to 90 and stay firm there, no matter how cold it is that is the thermostats job to keep it at 90

Well I'm lost then. I don't know what else to try!!?
 
Obviously when the dash gauge rises it should get to 90 and stay firm there, no matter how cold it is that is the thermostats job to keep it at 90

I haven't checked my coolant; perhaps I need to top it up
 
Unless you got an air lock?

I have actually removed coolant and put it back in so that could be quite plausible. There's some way of sorting that isn't there.. Is it unscrew the reservoir cap, put the engine on turn heater up to high and ??! I read it somewhere