Peugeot 308 CC - Falling apart now?

[CitroJim]

Excellent work-around Mike I like it!

[xantia_v6]

The replacement thermostat arrived today. Unfortunately I had not understood the complexities of supercession for this component.

Originally the temperature sensor was mounted with the heater, and there was a single 4 pin connector to both.
Then the thermostat housing was modified and the temperature sensor moved to the top of the housing. An adapter lead was then supplied to split the 4 pin connector into a 4 pin with only 2 pins used and a 2 pin flying lead to the relocated temperature sensor (this arrangement is currently fitted to the car, I suspect that it is a replacement).
Then they modified the design again, so that there are 2 2 pin connectors on the housing and a different adapter lead from the original 4 pin plug. This adapter lead is is BMW P/N 12518611289.

So I have a new thermostat, but can't fit it as I don't have the correct adapter lead.

The 2 pin plugs that I would need to 'adapt' the existing adapter lead seem to be generic Bosch compact connectors, and the same as used on the turbo dump valve and the PCV heater, but I have not yet been able to source any (new or used) locally.

[Edit] See later post regarding parts compatibility!

[RichardW]

Hope you found that out before you stripped it down....!!

Adaptor lead looks like Pug part no 9804315380 - they want £46 for it though!! If you can find scrap plugs and make your own lead, I would go that route...

[CitroJim]

Tell you what Mike, you've put me right off the 308 CC or anything with that engine What a bloody parlarva

[xantia_v6]

Hope you found that out before you stripped it down....!!

Adaptor lead looks like Pug part no 9804315380 - they want £46 for it though!! If you can find scrap plugs and make your own lead, I would go that route...

I had only removed the scuttle, (which is the worst piece of design I have seen for a long time) and the low pressure air pipes then I saw that the connectors were different before going any further.

That looks like the right part, about the same price as the BMW part (but different length leads and connector colours). I tried a could of car wreckers and an auto electrician, but they are full of Japanese stuff and couldn't find anything with Bosch connectors. I will try the Bosch Diesel service agent today. It doesn't help that most places here are closed for the christmas holiday.

[xantia_v6]

I spent half a day going around trying to find compatible connectors, but it seems that the compact oblong style of 2 pin connector was not used before about 2007, and I could not find any on scrapped cars.

I have now ordered a BMW adapter lead from the USA. There is an after-market BMW parts store that could possibly have provided one locally, but they are closed for their Christmas shutdown for another week, so I opted to import one directly.

[xantia_v6]

This just gets worse...
So I got a thermostat, then found I needed an adapter harness. Now when attempting to fit the thermostat, I have discovered that there is another version (P/N 1336 CC), which is of course the one that I require. This one seems to be a PSA-only part not used by BMW. The only significant difference is that the heater outlet connection takes a clip-on connector, not a hose clamp (it also has a different adapter harness, but the car already has one of those).

So now I need to refit the faulty thermostat and order yet another one.

1336 Z6 and 1336 CC (own work)

detail of 1336 CC heater hose connector (own work)

detail of 1336 Z6 heater hose connector (own work)

[CitroJim]

That's bloody annoying Mike

[Zelandeth]

I assume that the heater hose is too short to simply hack the clip connector off the end and attach it with a standard hose clip?

This is the sort of nonsense with similar-but-not-quite parts was why I ended up selling on my Renault 11TC. It was an odd model right on the phase 1 to phase 2 switchover and apparently had been built with whatever they had laying around on the factory floor - irrespective of if it was ever meant to have been used on an 11! It was a lovely little car to drive and in really good nick, but finding parts for it (even brake pads) was just such a gigantic headache that it had to go.

Have to admire your perseverance though, it really does seem to have fought you at every step this one.

[xantia_v6]

The car is now back together with the original part and the external resistor, a thermostat is on order from the UK (pattern part £50, dealer here wants equivalent of £250 for the part).

For future reference, changing the thermostat is quite fiddly, involving the removal of more components than the official procedure would suggest...

• Remove wiper arms and scuttle trim
• Remove both low pressure air pipes
• Remove the air filter
• Remove the battery, plastic support tray and loosen the metal support tray
• Lift the plastic bracket holding wiring harnesses over the thermostat to allow slightly better access to the hose fittings
• Remove all 5 hoses from the thermostat housing (note that several different types of clip and clamp are used) The plastic clip on the top heater hose looks fragile so be careful with it. I had to undo the turbo coolant pipe at the turbo end, as the flexible section is too short to slide off the spigot. In the process, you should probably disconnect the hoses from the vacuum pump to avoid damaging them.
• Remove the clip from the recirculation pipe behind the engine (study orientation first to aid later reassembly)
• Undo the 10mm nut at the top of the thermostat and the 8mm screws on each side.
• Extract the thermostat housing. This would be easier if the stud at the top were shorter, hence the need to loosen the battery support to give some more wiggle room.

[Zelandeth]

Oh lordy...

*Note to self - never buy one of these cars!*

I thought it was a faff when I stripped the threads in the head of my father's Fiat Panda and I had to tap the hole again!

[CitroJim]

*Note to self - never buy one of these cars!*

I made that note to myself long ago...

Mike, you're really not a good advert for these cars

[Michel]

For future reference, changing the thermostat is quite fiddly..

<snip horrific description>

Not only a master of Forum Admin, but a master of understatement too!

[CitroJim]

For future reference, changing the thermostat is quite fiddly..

<snip horrific description>

Not only a master of Forum Admin, but a master of understatement too!

Indeed...

[xantia_v6]

I finally got the thermostat replaced with a part that fitted. Same old procedure, but the main temperature sensor and adapter harness need to be swapped to the new thermostat housing, as the housing does not come with a sensor fitted.

Both of the replacement thermostat housings had a heater resistance of 15.5 Ohms but the faulty one had a resistance of 5.5 Ohms.

After warning people to take care about the clip on the recirculation pipe behind the engine, when i went to remove it, it was not there! so despite carefully (so I thought) fitting it, it must have been fitted incorrectly and pinged off into the ether somewhere... Fortunately, I don't think that the clip actually does anything, as it is clipping 2 solid pipes together, and neither of them seems to have any movement once the thermostat housing is fastened. Thinking it unlikely that I could obtain a replacement clip at short notice, and knowing that I did not want to dismantle everything again later to fit one, I fabricated a new clip by unrolling a coil spring* of about the right gauge and reshaping it for this application.

Another work of advice for working on these engines is because access is so tight, you usually have to uncouple several hoses and electrical connectors that are not related to the job at hand, and it is very easy to forget to refit one (especially the ones you cant see). I would advise making a written note of each disconnected item then tick them off when refitted. This time I forgot to reconnect the cam timing sensor. The engine runs without it, but takes a couple of seconds cranking to start while the ECU guesses which cylinder is on compression stroke, then it throws a fault code after the 3rd start.

One piece of good news is that after about 4000km running with the modified PCV system, there is no trace of oil in the PCV hose going to the turbo inlet, and you can wipe your finder around the turbo inlet and it comes away clean. So I don't think that the valves will need decarbonising any time soon.

* The spring that I recycled came from a bag of 20 that I recovered from a landfill site in about 1977. There was about a skip-full of bagged automotive brackets, nuts, bolts and fasteners which had apparently been dumped by the local Toyota assembly factory after a model change-over. I got about 50 assorted bags of useful looking bits, which still serve for general purpose fasteners. I think that these springs were probably handbrake return springs.