308cc (2009) Coolant Loss (internal) & Anti-pollution System Fault

[divettri]

Hi, I have recently bought (privately) a 2009 Peugeot 308cc. The car seems to run well however, there are 2 noticeable things. Engine is a 1598cc petrol:-

1. The coolant will go into low alarm, almost every week. Sometimes the level sits below the "low" marker, once, the tank was more or less empty. What do you suggest this could be & what should I do about it?

2. The Anti-pollution System Fault & Engine Management System Faulty warning has come on. The fault clears with a diagnostic reset but re-appear at any time. Any help or experience with this fault?

Some fault codes read are:-

P0016 $07e8 - CRANKSHAFT POSITION CAMSHAFT POSITION CORRELATION BANK 1 SENSOR A
P0299 $07e8 - TURBOCHARGER / SUPERCHARGER UNDERBOOST
P0299 $07e8pd - TURBOCHARGER / SUPERCHARGER UNDERBOOST

I didn't realise the vehicle had a Turbocharge / Supercharger??

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

Thanks for any help offered.

[Arkis]

Hello, if you can't find a leak, it will be probably headgasket failure. Check for gasses in the expansion tank. Remove cap from expansion tank, start engine and watch for bubbles. If the leak is smaller it might not make bubbles but you can use headgasket leak test. They are very inexpensive and accurate. I am buying set like this from Poland but I believe every bigger car parts dealer will have set like this.

If you're burning coolant, you are making emission much worse thus the anti-pollution light comes on.

1.6 petrols usually have turbos. The codes could be worn out turbo, carbon deposits in lines or low oil pressure. Are you using correct oil and are you changing it regulary?

P0016 means that signal from crank and cam is out of sync. Either wiring problem, sensor problem, variable valve selenoid malfunction/low oil pressure, or skipped timing.

[xantia_v6]

To isolate the coolant leak, you need to pressurise (to 1 bar) the cooling system with the engine cold and look carefully for leaks, especially around the thermostat where the plastic housing often cracks.

[jamie-n]

I had similar coolant loss to this recently, same Prince engine, no signs of leakage but the coolant bottle was emptying over the space of a few days, with the low coolant warning coming up on the dash
regularly, initially started thinking head gasket but it wasn't!, it was the thermostat housing, the leak was so fine it was virtually misting out and away once the temperature
was high enough, so no pools of water anywhere.

I decided it was a worth a try replacing the housing first before stripping the head off it, lo and behold it has held all it's coolant since.

There's a chance if you get right in to view all over the top of the gearbox you might just find a tiny pool of coolant
in one of the recesses just below or behind the housing itself.

One of the worst thermostat setups in the history of motoring. Possibly built intentionally to be problematical cash cow?

[PaulC5]

For the P0299 code check if the MAP sensor is bunged up with oil. If your code reader does live data you can see what values it is giving and if they change as the accelerator pedal is used which they should.

[divettri]

Hello, if you can't find a leak, it will be probably headgasket failure. Check for gasses in the expansion tank. Remove cap from expansion tank, start engine and watch for bubbles. If the leak is smaller it might not make bubbles but you can use headgasket leak test. They are very inexpensive and accurate. I am buying set like this from Poland but I believe every bigger car parts dealer will have set like this.

If you're burning coolant, you are making emission much worse thus the anti-pollution light comes on.

1.6 petrols usually have turbos. The codes could be worn out turbo, carbon deposits in lines or low oil pressure. Are you using correct oil and are you changing it regulary?

P0016 means that signal from crank and cam is out of sync. Either wiring problem, sensor problem, variable valve selenoid malfunction/low oil pressure, or skipped timing.

thanks for such a detailed reply. i do have some queries related to your answer though.

If you're burning coolant, you are making emission much worse thus the anti-pollution light comes on - How can i tell if i am burning coolant & what is the repair for this?

With regard to the Turbo, what can i do to check out this issue or issues as you suggest?

Regarding the P0016, what are the remedies for this? Is there anything I can do at home to eliminate anything too intrusive? I have cleaned the connectors of various sensors with electrical cleaner already.

[divettri]

To isolate the coolant leak, you need to pressurise (to 1 bar) the cooling system with the engine cold and look carefully for leaks, especially around the thermostat where the plastic housing often cracks.

hi, how do i do this?

[divettri]

I had similar coolant loss to this recently, same Prince engine, no signs of leakage but the coolant bottle was emptying over the space of a few days, with the low coolant warning coming up on the dash
regularly, initially started thinking head gasket but it wasn't!, it was the thermostat housing, the leak was so fine it was virtually misting out and away once the temperature
was high enough, so no pools of water anywhere.

I decided it was a worth a try replacing the housing first before stripping the head off it, lo and behold it has held all it's coolant since.

There's a chance if you get right in to view all over the top of the gearbox you might just find a tiny pool of coolant
in one of the recesses just below or behind the housing itself.

One of the worst thermostat setups in the history of motoring. Possibly built intentionally to be problematical cash cow?

hi, are you able to show me on a photo where i can find this housing & also you go about replacing it?

[divettri]

For the P0299 code check if the MAP sensor is bunged up with oil. If your code reader does live data you can see what values it is giving and if they change as the accelerator pedal is used which they should.

hi, please can you advise where i can find the MAP sensor please so i can check?.

My OBD2 is a handheld unit but does display some live data so i will check. Is it obvious on the OBD2 the data i need to check? How do i know if it is correct if it is changing as accelerator is pressed?

[Arkis]

If your car is burning coolant in a matter of days you will see white smoke coming from exhaust (don't mix it up with condensation that occurs during warming up of exhaust during cold days). One of big giveaways of burning coolant is that the white smoke is usually almost like sweet.

Thermostat housing is located on right side of the engine (above transmission). You will easily find it by tracing coolant hose from the radiator. If you're lucky enough, there will be aluminium alternative for your housing. This is for example on my 206 TU3JP (year 2005).

[xantia_v6]

To isolate the coolant leak, you need to pressurise (to 1 bar) the cooling system with the engine cold and look carefully for leaks, especially around the thermostat where the plastic housing often cracks.

hi, how do i do this?

You can buy a pressure tester with a hand pump, gauge and adapters something this:



I got an army surplus one at little cost which although 50 years old, does fit the PSA coolant bottle.

If replacing the thermostat housing, be very careful to get the correct part, as there are at least 5 variants for the THP engine, with slight differences to the hose connections or electrical fittings. To make it worse, for early cars (like yours) the original part was superseded by a later version which has different electrical connections and an adapter harness is also required (although your car may have this if it has previously been changed).

[divettri]

If your car is burning coolant in a matter of days you will see white smoke coming from exhaust (don't mix it up with condensation that occurs during warming up of exhaust during cold days). One of big giveaways of burning coolant is that the white smoke is usually almost like sweet.

Thermostat housing is located on right side of the engine (above transmission). You will easily find it by tracing coolant hose from the radiator. If you're lucky enough, there will be aluminium alternative for your housing. This is for example on my 206 TU3JP (year 2005).

Hi, please can someone advise where to look for this thermostat valve (images attached)? Not much room in the engine bay to be honest.

Also noted was the exhaust blowing a bit of white smoke, not sure if this means anything or whether the car was just cold at the time?

[Arkis]

Follow this coolant line and you will find it. The coolant hose from upper radiator is directly attached to the thermostat housing.

White smoke from exhaust can be condensation or burning coolant. If it is still smoking after engine is up to temperature it is most likely burning coolant and you should do headgasket test.

[PaulC5]

For the P0299 code check if the MAP sensor is bunged up with oil. If your code reader does live data you can see what values it is giving and if they change as the accelerator pedal is used which they should.

hi, please can you advise where i can find the MAP sensor please so i can check?.

I believe the MAP sensor is on the intake manifold at the back of the engine if it is the same as a C4 1.6 petrol engine as shown in the C4 Haynes manual. However, looking at your engine pictures it might be on the large black inlet pipe at the left of the photo. To find out what it looks like, look on a site such as eurocarparts with your car details. If you do buy one to ensure it is correct you might be best to buy from a Peugeot dealer. Also make sure any seal on it is in good condition. On live data just see if its value changes as the accelerator pedal is used.

[xantia_v6]

The sensor on the pipe on top of the engine is the boost sensor. The MAP sensor is mounted on the manifold or throttle body.