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        General >> Problems >> Temp Gauge Not work Correctly
        
(Message started by: mondeoman on Feb 26th, 2011, 11:54am)
Title: Temp Gauge Not work Correctly
Post by mondeoman on Feb 26th, 2011, 11:54am

I know it's that odd chestnut again of the temp gauge showing cold when the engine is warm and then suddenly rise briefly, before failing back to cold etc.

Well I've changed the sensor which has not solved the problem.

I've currently got the instrument cluster out and no apparent sign of a large amount of solder present as indicated in the instructions found else where on the site.

It's an early facelift 2.3 Ultima.

I'm now a bit stumped as what to do next. I wonder if I should get a replacement instrument cluster and see if that solves the problem?

Would that be the next step to try?
If I did do that well I get any problems with the coolant light staying on etc as this is shorted out on this car?

Cheers,

Simon
Title: Re: Temp Gauge Not work Correctly
Post by scorpio_man on Feb 26th, 2011, 2:52pm
Hi there

did you check what the actual temp was using the dash daignostics?

did you replace the correct sensor?

hth
Title: Re: Temp Gauge Not work Correctly
Post by Jonnycab on Feb 26th, 2011, 5:26pm
Have you checked the wiring from the sensor ?...That part of the engine loom (like the top part) also tends to suffer from brittle/broken insulation causing shorting wires  :)
Title: Re: Temp Gauge Not work Correctly
Post by Snoopy on Feb 27th, 2011, 8:04am
The BIG multi pin plug on the inner wing ( offside) usually causes the symptoms that you describe. Its well worth taking apart ( small 10mm nut to undo) and cleaning the pins with electrical contact cleaner. I had the very same symptoms on my scorpio for a couple of years until I diagnosed the problem.
Title: Re: Temp Gauge Not work Correctly
Post by mondeoman on Feb 27th, 2011, 7:22pm
I have already cleaned the multiplug with contact cleaner, so I'll have to check the wiring in more detail and see if I can find anything.

I must admit the insulation seemed to be ok to me on the multiplug.
Title: Re: Temp Gauge Not work Correctly
Post by Tompion on Feb 27th, 2011, 8:03pm
Possibly a thermostat problem, they can play havoc with the temp gauge, reading the output via OBD is the best way, it’s difficult to tell the difference between a hot and warm engine via the gauge.

Some time ago when I compared the gauge reading to the ECT the gauge didn’t appear to move in a very linear way.
Title: Re: Temp Gauge Not work Correctly
Post by mondeoman on Mar 6th, 2011, 7:26pm
I've tried another instrument cluster in the car and that did not resolve the problem. If the front sensor on the engine is the temp gauge then I've also replaced that which has not solved the problem.

When you mention the mulitplug being cleaned I assume it is one of the two next to the engine on the drivers side? If so then I've also cleaned them with contact cleaner.

The gauge did work briefly and when I switched the engine off and put the ignition straight back on I noticed the gauge started to drop.

I have to say the wires all seem to be in very good condition, no problems with the insulation etc.

Cheers,

Simon
Title: Re: Temp Gauge Not work Correctly
Post by Mike H on Mar 7th, 2011, 3:16pm
Well that proves the actual gauge was OK.

The dashboard diagnostic test for it is step No. 5 here:

http://www.fordscorpio.co.uk/instreset.htm
Title: Re: Temp Gauge Not work Correctly
Post by Mike H on Mar 7th, 2011, 3:19pm
PS: sure it's not just because of the time of year? Mine is hardly off the blue in this weather unless I leave it idling for 10 minutes or something
Title: Re: Temp Gauge Not work Correctly
Post by Tompion on Mar 7th, 2011, 3:30pm
How hot is the top hose to the rad? It may warm slightly due to coolant getting past the bleed hole/valve but it shouldn’t start to get hot until the stat begins to open at 88C.

It is possible to have the stat fitted the wrong way round on the 2.3
Title: Re: Temp Gauge Not work Correctly
Post by Jonnycab on Mar 7th, 2011, 4:47pm
Just a thought....your rad fans aren't on permanently are they ?  :)
Title: Re: Temp Gauge Not work Correctly
Post by lleewar on Mar 8th, 2011, 11:00am
Just purchased another 2.0 ultima and have the same problem. At speed the guage dropped to near the lower white line, stayed for a while then returned.  Put on the heating and the guage dropped down again. Must admit at full pelt it was not very hot. Sludge around thermostat, clean/replace. Will put thermostat on boiling water check to make sure it is working.  Lee
Title: Re: Temp Gauge Not work Correctly
Post by Jonnycab on Mar 8th, 2011, 3:03pm
Temp guage dropping on a run & then reading normal when plodding around town indicates a faulty thermostat.

Has anyone tried bleeding all the air out of the system, as just a small pocket of air trapped behind the thermostat or around the temp gauge sensor can cause the temp gauge to act strangely.

I've sometimes found these cars to be difficult to remove all the air, so I use THIS (http://www.fordscorpio.co.uk/cgi-bin/yabb/YaBB.pl?board=admin;action=display;num=1267895712) method & it always works wonders  :)
Title: Re: Temp Gauge Not work Correctly
Post by lleewar on Mar 8th, 2011, 5:12pm
Thanks Jonny, great idea. Will try that one and will report back.  Lee
Title: Re: Temp Gauge Not work Correctly
Post by Mike H on Mar 9th, 2011, 1:14pm
Occurred to me my thermostat is probably getting old and tired by now speshly if it's still the original!

Did the dash diag thing on it after a run out today and with needle in the centre it came back '114', which is fair enough.
Title: Re: Temp Gauge Not work Correctly
Post by Tompion on Mar 9th, 2011, 1:50pm
How does that test the stat?
Title: Re: Temp Gauge Not work Correctly
Post by Mike H on Mar 9th, 2011, 3:05pm
It doesn't. ;D
Title: Re: Temp Gauge Not work Correctly
Post by PJDavis on Mar 9th, 2011, 6:37pm
I think I had a similar problem a while ago.   I replaced the thermostat, and all problems went.   I also did a pictorial change and it was moved to 'How to do things'.   Made a difference to my 2.3.   I spent a LONG time removing the air from the system, aye, much longer than I expected and I'm an 'old-fashioned' mechanic.  
Title: Re: Temp Gauge Not work Correctly
Post by SnowyScorpio on Apr 28th, 2011, 11:00pm

on 03/07/11 at 15:19:49, Mike H wrote:
Mine is hardly off the blue in this weather unless I leave it idling for 10 minutes or something


I have had the same problem but have sorted it out (almost anyway) by insulating the sensorcluster on the pipe from the wind with some standard house insulation.

//Snowy
Title: Re: Temp Gauge Not work Correctly
Post by Highlander on Jun 21st, 2011, 11:18am
Simon, been thinking about this one, have you looked at the thermostat?

it may be sticking or even missing altogether?

Was the gauge reading ok previously or has it been like that since you got the car?
Title: Re: Temp Gauge Not work Correctly
Post by mondeoman on Jun 26th, 2011, 1:14pm

Stuart,

I've not even looked at the Thermostat, but the problem has occurred since we bought the car. The strange thing is that it does work for a little while before it drops back to cold, but the length of time it takes for this to happen etc seems to vary.

I thought the Thermostat did not have anything to do with the temp gauge, or that's what I was lead to believe by some people on here.
Title: Re: Temp Gauge Not work Correctly
Post by Tompion on Jun 26th, 2011, 3:10pm
The thermostat was suggested earlier in this thread ;)
Title: Re: Temp Gauge Not work Correctly
Post by Highlander on Jun 26th, 2011, 9:19pm

on 06/26/11 at 13:14:48, mondeoman wrote:
I thought the Thermostat did not have anything to do with the temp gauge, or that's what I was lead to believe by some people on here.


Well they arent connected as such but if your thermostat sticks open (or is missing) the  temp gauge will read low, if it sticks shut the temp will rise
Title: Re: Temp Gauge Not work Correctly
Post by Eric_B. on Jul 26th, 2011, 8:53pm
I have the exact same problem and no solution.
Title: Re: Temp Gauge Not work Correctly
Post by Snoopy on Jul 27th, 2011, 8:20am
From my understanding of the data on the dashboard diagnostic The Numbers on the dash display are NOT actual temperatures. The numbers refer to a logarithmic scale between 20 and 255 which is what the ecu requires in data form.....
Quote:
This checks the engine coolant temperature sensor as a data signal between 20 to 255, disproportionate to temperature (i.e., high temp, low data number)

S-C means sensor is out of normal range.

When the temperature gauge needle is horizontal the display should read between 79 to 129

37              Maximum temperature

57              Bottom of red chaplet

79 to 159  Middle of Normal band

242            Middle of blue chaplet

255            Bottom  


See The whole dash test procedure and the meanings HERE (http://www.fordscorpio.co.uk/instreset.htm)
Title: Re: Temp Gauge Not work Correctly
Post by Mike H on Jul 27th, 2011, 6:57pm
That is my understanding also


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