Coolant temperature erratic
Moderator: RichardW
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Coolant temperature erratic
Thanks to the Lexia, I've noticed the ECT sensor is reporting erratic temperatures, showing a huge range from as low as -34 to +145 when I guess the true temperature was about 20-90 as it warmed up on idle.
I think I made it worse by wiggling the wires close to the connector but is it usual (within the ECT sender spec) to show such a wide range of temperatures - given such conditions or does it point to a more serious problem like failing ECU?
I think I made it worse by wiggling the wires close to the connector but is it usual (within the ECT sender spec) to show such a wide range of temperatures - given such conditions or does it point to a more serious problem like failing ECU?
- KennyW
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Hi Mike,
Could it be the sensor on the fuel filter housing/thermostat not earthing correctly.
Kenny
Could it be the sensor on the fuel filter housing/thermostat not earthing correctly.
Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, the newbie
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
- KennyW
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Hi Mike,
I have a problem with mine which is. The temp gauge does not work for long periods especially during the winter but as spring arrives it suddenly works for a short time then stops even during a short journey.
Kenny
I have a problem with mine which is. The temp gauge does not work for long periods especially during the winter but as spring arrives it suddenly works for a short time then stops even during a short journey.
Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, the newbie
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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Hi Kenny,
The engine coolant temperature sender and the dash gauge sender are individual parts - Green = dash gauge, Brown = Bitron and Blue = ECT.
I've just been out for a quick looksee and I'm 99.9% sure it's the sender itself as with it disconnected, the Lexia shows a constant -45 (In hindsight, I should have checked to see if it logged a fault code too ) and with my multimeter hooked up to the sender, it read correctly until it got warm/hot then all hell broke loose - readings all over the shop, hence my certainty the sender is fubar'd.
The engine coolant temperature sender and the dash gauge sender are individual parts - Green = dash gauge, Brown = Bitron and Blue = ECT.
I've just been out for a quick looksee and I'm 99.9% sure it's the sender itself as with it disconnected, the Lexia shows a constant -45 (In hindsight, I should have checked to see if it logged a fault code too ) and with my multimeter hooked up to the sender, it read correctly until it got warm/hot then all hell broke loose - readings all over the shop, hence my certainty the sender is fubar'd.
- KennyW
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Thanks Mike,
Where is the gauge sensor located
Kenny
Where is the gauge sensor located
Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, the newbie
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
- CitroJim
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That'll be affecting your timing Mike as the engine ECU uses the ECT temperature to determine things..
Strange it's the blue sensor on Diesels. On petrols the ECT sensor is always the green one.
French logic is bizarre at times... "Oui Jacques, the ECT is Bleu and therefore a diesel!!!"
Strange it's the blue sensor on Diesels. On petrols the ECT sensor is always the green one.
French logic is bizarre at times... "Oui Jacques, the ECT is Bleu and therefore a diesel!!!"
Jim
Runner, cyclist, time triallist, duathlete, Citroen AX fan and the CCC Citroenian 'From A to Z' Columnist...
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Yes Jim, was interesting to watch the live parameters, it's the timing that drew my attention to the temperature as it happens. I was watching it slowly retard as the engine warmed up then it suddenly raised to 7 or more degrees and the subsequent knocking had me concerned. When I saw the coolant changing from 70's, 60's, 10's, 70's, 50's etc I saw the connection. Great things these tools!CitroJim wrote:That'll be affecting your timing Mike as the engine ECU uses the ECT temperature to determine things..
Strange it's the blue sensor on Diesels. On petrols the ECT sensor is always the green one.
I might be sort of colour blind when it comes to some shades of green and blue - so, let's just say my ECT is the one at the back
- CitroJim
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Lexia rules Bloody handy aren't they Mike! Without one you'd have never spotted that...
My memory might be the dodgy party here though...
Ahh, now if memory serves me correctly and it's been a while since I had a 1.9TD now but I fancy the one at the back is a green one.MikeT wrote: I might be sort of colour blind when it comes to some shades of green and blue - so, let's just say my ECT is the one at the back
My memory might be the dodgy party here though...
Jim
Runner, cyclist, time triallist, duathlete, Citroen AX fan and the CCC Citroenian 'From A to Z' Columnist...
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- KennyW
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Xantia 1.9 TD estate - x 132
Thanks Jim and Mike,
If that sensor is faulty would that explain my running issues.
Kenny
If that sensor is faulty would that explain my running issues.
Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, the newbie
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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- Posts: 4809
- Joined: 11 Jun 2007, 16:17
- Location: Christchurch, Dorset. UK
- My Cars: 2005 C5restyle 1.6HDI 16v 110hp VTR Estate
2008 C5 X7 1.6HDI VTR+ Saloon - x 231
The dash gauge sensor (blue) has no part in engine management. It is purely for the driver's information.
If your Bosch pump has full timing control (as mine does), the green (rear) sensor is the one to check.
To test any of them; Connect a multimeter to the sensor pins, set the scale to resistance and run the engine. As the coolant warms, the resistance changes (drops I think). Check the change for smooth progression.
Mine starts off normal but goes haywire after a while.
If your Bosch pump has full timing control (as mine does), the green (rear) sensor is the one to check.
To test any of them; Connect a multimeter to the sensor pins, set the scale to resistance and run the engine. As the coolant warms, the resistance changes (drops I think). Check the change for smooth progression.
Mine starts off normal but goes haywire after a while.