Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

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BadIdea
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Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by BadIdea »

Hi all,

I think I need to change the thermostat on my 407 so I'm doing a bit of research before I start buying things and wielding spanners.
  • Am I best going for a thermostat on its own, or one with housing? Any recommendations on which brand to go for?
  • Is it worth replacing the coolant completely? Recommendations on brand?
  • Any guides, advice or gotchas for this particular car/engine?
Thanks

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white exec
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Re: Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by white exec »

Please post your VIN, so we can home in on the correct parts.

BadIdea
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Re: Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by BadIdea »

The VIN is VF3**************[VIN obfuscated, can be read by forum staff]

Thanks

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Re: Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by BadIdea »

For BMWs I've always used realoem.com to get part numbers and view diagrams, is there anything similar for Peugeots that's publicly accessible?

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white exec
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Re: Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by white exec »

Yes - go to service.citroen.com, and register as an Independent Repairer.
This will give you access to Citroen, Peugeot, and now Vaux/Opel parts info, and much else.
You'll need your VIN, which can be entered to get data for exactly your vehicle.
Can also search by Part Number (omit any spaces or full-stops, eg for 9876.XY, input 9876XY), to be able to see what other vehicles a part was fitted to ('Run Search on All Vehicle Families').
NFP next to a part means 'no further production', and almost certainly unavailable from PSA.

Someone here will be able to advise of 'stat part/replacement for this engine, who knows it better than I do.

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GiveMeABreak
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Re: Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by GiveMeABreak »

BadIdea wrote:
13 Jan 2020, 23:59
Hi all,

I think I need to change the thermostat on my 407 so I'm doing a bit of research before I start buying things and wielding spanners.
  • Am I best going for a thermostat on its own, or one with housing? Any recommendations on which brand to go for?
  • Is it worth replacing the coolant completely? Recommendations on brand?
  • Any guides, advice or gotchas for this particular car/engine?
Thanks
This is the outlet tank setup on your vehicle:
407 thermo.PNG
Part 1336Y9 for the complete housing. Currently £151.16 inc. VAT from Peugeot. There are aftermarket parts, of varying quality.

Or you can get the sensor (item 2) separately, part 1338C1, £49.63 inc.

BadIdea
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Re: Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by BadIdea »

Thanks

Great, thanks. Do I need to buy the complete housing for this model? Any aftermarket brands that have a good reputation around here?

BadIdea
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Re: Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by BadIdea »

white exec wrote:
14 Jan 2020, 11:23
Yes - go to service.citroen.com, and register as an Independent Repairer.
This will give you access to Citroen, Peugeot, and now Vaux/Opel parts info, and much else.
You'll need your VIN, which can be entered to get data for exactly your vehicle.
Can also search by Part Number (omit any spaces or full-stops, eg for 9876.XY, input 9876XY), to be able to see what other vehicles a part was fitted to ('Run Search on All Vehicle Families').
NFP next to a part means 'no further production', and almost certainly unavailable from PSA.

Someone here will be able to advise of 'stat part/replacement for this engine, who knows it better than I do.
Nice one, thanks.

I've signed up but they seem to have some sort of security in place based on location.

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GiveMeABreak
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Re: Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by GiveMeABreak »

BadIdea wrote:
14 Jan 2020, 21:39
Thanks

Great, thanks. Do I need to buy the complete housing for this model? Any aftermarket brands that have a good reputation around here?
It depends what's wrong with it. Have you had it diagnosed - any fault codes?

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white exec
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Re: Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by white exec »

BadIdea wrote:
14 Jan 2020, 21:44
I've signed up but they seem to have some sort of security in place based on location.
Security is fairly strict on service.citroen.
The system looks for a match between the user's IP address and their declared location.
Got caught with this once, when google screwed up, and placed me in Ukraine.
Was locked out by Citroen, but they asked me to check how google was locating me (at bottom of google homepage, iirc), and as soon as this was rectified, up and running again ok.
They are keen that accounts are not hijacked.

New accounts might take a day or so to be authorised and fully open.

BadIdea
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Re: Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by BadIdea »

GiveMeABreak wrote:
14 Jan 2020, 21:50
BadIdea wrote:
14 Jan 2020, 21:39
Thanks

Great, thanks. Do I need to buy the complete housing for this model? Any aftermarket brands that have a good reputation around here?
It depends what's wrong with it. Have you had it diagnosed - any fault codes?
I haven't yet, but the symptoms are low water temp even after 40 mins of driving, barely any heat through the cabin when the climate is set to 28c, and considerably lower economy than I would expect (27mpg over 30 miles or so of mixed driving).

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GiveMeABreak
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Re: Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by GiveMeABreak »

Don't forget the possibility of the heater matrix too. That could be full of gunk and stopping the hot water from circulating into the cabin heater matrix when it gets blocked.

BadIdea
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Re: Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by BadIdea »

white exec wrote:
14 Jan 2020, 22:56
BadIdea wrote:
14 Jan 2020, 21:44
I've signed up but they seem to have some sort of security in place based on location.
Security is fairly strict on service.citroen.
The system looks for a match between the user's IP address and their declared location.
Got caught with this once, when google screwed up, and placed me in Ukraine.
Was locked out by Citroen, but they asked me to check how google was locating me (at bottom of google homepage, iirc), and as soon as this was rectified, up and running again ok.
They are keen that accounts are not hijacked.

New accounts might take a day or so to be authorised and fully open.
I suspected my VPN might have been something to do with it. I'll try emailing tomorrow. Ironic that they're so keen on security and yet their SSL isn't working :-D

BadIdea
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Re: Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by BadIdea »

GiveMeABreak wrote:
14 Jan 2020, 23:27
Don't forget the possibility of the heater matrix too. That could be full of gunk and stopping the hot water from circulating into the cabin heater matrix when it gets blocked.
Hmm, something to think about. Would you expect the other symptoms too in this case, though? Although, from other posts it does seem common for Peugeot HDi engines to run cool/report low temps. The fuel economy seems way off (assuming the display is remotely accurate); I would have seen similar MPG from my M3 over the same journey, which can't be right.


Is there a part code for the thermostat on its own? Or does Peugeot not supply the thermostat separately? Prices seem to range from £20 to £150 for the full housing. I'm wary of going for the cheapest units, but if there are good value alternatives to the OEM part then I'm happy to give them a go. Likewise if there is a decent thermostat that can be bought on its own (assuming there isn't some gotcha relating to the installation).

ekjdm14
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Re: Peugeot 407 SW 2.0 HDi 136 Thermostat Replacement

Post by ekjdm14 »

The MPG figure does seem more than a tad low & that'd be my primary concern (our GTi180 manages about 29mpg on a run), but it'd be helpful to see what the coolant temperature really is (IR gun measurement at the thermostat housing) compared to what the ECU is seeing/reporting. If you have a cheap temperature gun you could check it yourself, they're less than a tenner on ebay & very useful little tools. You can even get an idea of flow by checking either side of the 'stat housing and comparing the readings. Obviously if it's stuck open then both sides will warm up equally slowly from a cold start whereas if it's functional you should see the head side getting warmer and then eventually see the top hose start to heat up as it opens.

Honestly I wouldn't spend even the £20-150 (+ the time and hassle) to replace the thermostat without a clearer picture of what was going on, tempting as it may be to leap in and shoot the prime suspect, that approach can lead down an expensive road. For what it's worth, I'd suggest the money would be better put towards a diagnostic session at a dealer or specialist if there's no-one local able to help with that. Offer of my help still stands as per the other post, if you happen to be down this way, fingers crossed there's someone a little closer though as it's not a short trip.