Thermostats - troubleshooting

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antb1981
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Re: Thermostats - troubleshooting

Post by antb1981 »

Peugeot have quoted £532, and other garages are estimating £350 without adapter lead and labour, but would need to see the car first.
Bit stuck as the car is a 08 plate and probably would not be worth spending that amount on , which is a shame as it's only done 24k miles.
Thinking about just changing the thermostat and not worrying about the electric side of the thermostat valve, and just connecting the temp sensor and see what happens.
Thanks Anthony
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white exec
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Re: Thermostats - troubleshooting

Post by white exec »

I'm not able to help with a wiring diagram for that part of your 308, linked to your VIN above, but hopefully someone here can unearth one.
Chris
antb1981
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Re: Thermostats - troubleshooting

Post by antb1981 »

Hopefully if anybody can help that would be much appreciated. Thanks for trying chris.
Thanks Anthony
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GiveMeABreak
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Re: Thermostats - troubleshooting

Post by GiveMeABreak »

Hi Anthony, the was an issue with these outlet tanks that affected Euro 5 emission control standard EP engines - where there was an incident linked to the engine coolant temperature sensor.

So although you have a leak and may not have the related temperature sensor issues, as you have found a replacement unit is likely to be the modified type and this is where your problem may be in the connections. I have put a little info here on the modification for a C5 X7 with this engine type - that was typical of some of the EP engines used across the range.

Depending on the engine, there are different coolant outlet housing assemblies:
  • The number of outlets depends on the type of engine (naturally aspirated or turbocharged) and the gearbox (manual or automatic).
  • The presence on the production assembly of a clipped or integrated engine coolant temperature sensor (This assembly may already have been modified in after sales)
Be aware that different modifications have been applied depending on the version.

Naturally aspirated EP engines
Assembly of a coolant outlet housing with clipped engine coolant temperature sensor:
  • Manual gearbox, from RPO number 13540
  • Automatic gearbox, from RPO number 13583
Turbocharged EP engines
  • Assembly of a coolant outlet housing with engine coolant temperature sensor installed in place of the bleed screw.
The repair was only needed for vehicles which had assembly 'C':
Coolant A.PNG
Coolant B.PNG
Coolant C.PNG
"A": Coolant outlet housing with removable engine coolant temperature sensor
installed next to the bleed screw:
Fitting correct
No operation is necessary.
"B": Coolant outlet housing with integrated
engine coolant temperature sensor
and engine coolant temperature sensor
fitted with a wire installed in
place of the bleed screw:
Fitting correct, no operation is necessary.
"C": Coolant outlet housing with integrated
engine coolant temperature sensor
and bleed screw: Incorrect fitting, carry out the repair.
For models with version 'C' in the table, the repair was to fit the engine coolant temperature sensor in place of the bleed screw and this would then require the modified harness. This example was for the same issue on an X7 - but applied to other models. So I'm not sure a wiring diagram is going to help here if it is a matter of undertaking the modification.
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Marc
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xantia_v6
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Re: Thermostats - troubleshooting

Post by xantia_v6 »

I am a bit confused about which version of thermostat your car currently has. I thought that they all had both a temperature sensor (or two) and an electric heater element, and despite all the variants of housing, there was always a 4 pin connector on the vehicle witring harness that either plugged directly onto the thermostat housing (early crs) or via one of the adapter harnesses (later cars). Does your housing not have the heater socket behind and below the main housing?

You will find most of my knowledge of these things sprinkled on a couple of pages in my blog following: viewtopic.php?p=560234#p560234
Last edited by xantia_v6 on 07 Apr 2020, 00:19, edited 1 time in total.
Reason: spelling
antb1981
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Joined: 30 Mar 2020, 21:29

Re: Thermostats - troubleshooting

Post by antb1981 »

Thanks for everyone's help so far, will try and get some pictures of thermostat on car tommorrow. Thanks again
Anthony
antb1981
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Re: Thermostats - troubleshooting

Post by antb1981 »

Hi there here are the pictures of my engine and thermostat. Also there is no bleed screw on it and the picture is of coolant sensor with a 2 pin plug which is vertical position.
Attachments
20200407_091742.jpg
20200407_091333.jpg
20200407_091750.jpg
20200407_091322.jpg
20200407_091309.jpg
20200407_091242.jpg
antb1981
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Joined: 30 Mar 2020, 21:29

Re: Thermostats - troubleshooting

Post by antb1981 »

Hi thanks Marc, version A thanks for pictures have found bleed screw hidden, and now have found extra 2 pin plug, doh what a donut. Thanks for everyone's help. I'll get new thermostat ordered, and also the rear pipe as I believe this fails quite frequently when replacing thermostat.
Thanks again Anthony
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GiveMeABreak
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Re: Thermostats - troubleshooting

Post by GiveMeABreak »

Well located Anthony - I must admit that's a pretty crammed engine bay!
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Marc
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Re: Thermostats - troubleshooting

Post by Dustysweeper »

I'm so glad I found this thread, some really great info in here. It seems I have thermostat issues on my Grand Picasso.

When I first got the car the temperature gauge would sit at the half way mark and if it climbed higher the fans would kick in. Cabin heat was great too.

Now the gauge never gets to the half way point and when idling the gauge will drop to zero after 5 minutesor so. Cab heat more or less disappears too until I start driving again. I now know where to look once I get the correct part.