Smoke from engine bay - 308 2Lt HDI Auto

W

Whippet

Well-known member
VIP Paid Subscriber
Fellow Frogger
Joined
Jun 7, 2011
Messages
1,672
Location
Ballarat
Hi. My daughters 308 2Lt HDI occasionally generates smoke that exhausts from the front of the bonnet. It has done this several times now during a 12+ month period. Yesterday I was able to inspect the engine within 15 minutes of this occurring. The vehicle had been driven across town for 15 minutes, so when parked was at full operating temperature. As per previous occasions I could not identify a cause or source. The smoke smells like hot oil vapour. The engine is not overheating, There are no external oils leaks onto the ground. There are no external oil leaks on/around the engine, that I can see. The engine oil on the dipstick is approx 7mm overfull from the upper mark, but the smoke was occurring prior to the vehicle being serviced by a local mechanic, so I don't suspect the overfull sump as the cause. Vehicle has done 230,000km.

I suspect that engine oil is getting onto hot components and vapourising to smoke. It is difficult to gain access and to see in behind the engine where the exhaust and turbo are located. My second theory is that I have observed there is a fair bit of crankcase blowby & oil getting into the inlet plumbing to the turbo inlet. Once the engine is at operating temperature and the vehicle is parked, heat soaks across from the turbine to the compressor side of the turbo and the surface temperature is hot enough to fume/smoke the oil coating the wetted areas of internal plumbing. This then increase volume in the inlet duct and comes out via the air cleaner element. Then vents out the front of the bonnet area.

Does anybody have experience with these engines? Has anyone seen this occur?

I have a short MP4 video of the smoke, but can't attach this file.
 
308s have been around a while,and it's a high mileage car. The engine code would help.

If you have a site you can post a file to, you can link to it from here.
 
Check oil leak onto the turbo or out of a turbo seal. Happened with my ex 406 2l HDI wagon, amongst many other issues.

As well oil being overfull is not recommended as this can cause un-desireable foaming.
 
Last edited:
Get it checked out quickly.
Where there is smoke, there will be fire if oil get's hot enough to ignite about 200degC.
Oil ignition Temp
Turbo temps 1000 DegC
 
rocker cover gasket may be leaking onto the exhaust manifold ,if you can get your hand over the back when its cold ,run your fingers along under the join to see if there's oil there ,the cat will hide any oil going into the exhaust ,the pipe feeding oil to the turbo may be cracked or split spraying onto the exhaust ,but with the pressure there i suspect it would be showing elsewhere also ,im not sure on models but a friend had his catch fire when a pre heater on the fuel line ,located between the engine and the firewall drivers side .split, spraying deso onto exhaust ,he said people were waving him down when driving ,he thought it was doing its de frag thing until the red light went on ,the fire burnt through the heater hose ,the spray put the fire out lucky .big mess ,so yes get it checked pronto ,
 
pugwash said:
rocker cover gasket may be leaking onto the exhaust manifold ,if you can get your hand over the back when its cold ,run your fingers along under the join to see if there's oil there ,the cat will hide any oil going into the exhaust ,the pipe feeding oil to the turbo may be cracked or split spraying onto the exhaust ,but with the pressure there i suspect it would be showing elsewhere also ,im not sure on models but a friend had his catch fire when a pre heater on the fuel line ,located between the engine and the firewall drivers side .split, spraying deso onto exhaust ,he said people were waving him down when driving ,he thought it was doing its de frag thing until the red light went on ,the fire burnt through the heater hose ,the spray put the fire out lucky .big mess ,so yes get it checked pronto ,
Click to expand...
Hi pugwash.

Thanks for your comments. I have inspected the engine area and cannot locate an obvious external oil leak, but I can't easily access the exhaust / turbo area between engine and firewall. If there was a spray from turbo oil feed I would expect a lot more oil to available, but there are no drips anywhere on the driveway or under the vehicle. Also the smoke comes out the left side of the front of bonnet. If smoke was from the exhaust/turbo area I would anticipate it to vent at the rear of the bonnet as it is higher than the front.

Engine still starts, drives and performs well.

I still think that the oil smoke is coming out the inlet tract from the air cleaner, hence the front left location. So it has to involve oil and heat. One source of oil is from the turbo bearings oil seals, could this be occurring on the hotter turbine/exhaust side and the vapour going through a cylinder with both valves open and then back through the turbo compressor/inlet side then back out the air cleaner. Seems a labyrith path? Also it doesn't do this all the time, only infrequently.

Thinking as I am typing, I think I will discount the above theory, as how would the oil smoke get past the air filter element??? I don't think it would, unless it was perforated. I will have to have a more thorough investigation when the vehicle is next available, it is my daughters car.

This was a popular engine in 307, 407 & 308, and I had hoped that this may have been a known issue from someone on this forum.

A friend had his 406 diesel catch fire in the engine bay, not sure of the cause.
 
i just went out to have a look at my wifes 06 307 to see what's in that area ,only to find our little fury friends the bush rats have taken up residence above the battery! ,the intercooler is in that area left front ,is it possible the boost hose is split or loose ,her car in the past has had oil leaks [drips] were the plastic pipe that runs under the engine meets the rubber one going onto the bottom of the intercooler ,just needed the clamp doing up ,so there is oil vapour in that pipe ,wax bait tied onto chassis rail ,i have had them in my ducato for a while now[ baits ] and have to regularly replace them ,no damage to van ,they the rats must have suddenly developed a taste for French food
 
308 RHR Fault Codes.jpg
 
Hi. My daughter commenced driving to Melbourne on Friday AM. after 12 km on freeway the car displayed the Depolution Fault message, also has Engine icon displayed. So she turned around and left the car at home and borrowed another car. Only just looked at the car this evening. I discovered the 13 fault codes in above post. This seems to be a lot of codes, I don't understand why so many all at once.

I tried to delete them but was unable to achieve this. Any thoughts why this cant be done?

Just took the car for a 25km drive and seems to drive OK, with acceptable acceleration.
 
have fault codes been deleted in the past ,these faults could have accumulated over some time ,delete codes and have the battery checked ,how old is the battery ?
 
Hi Pugwash. I have never had any reason to check or delete codes previously, until the Depolution Fault message displayed recently.
Diagbox seems unable to delete them.
I will need to check the records for the battery. I will also check the voltage while cranking.
 
Regarding the Battery. All measurements are in volts, on extension cable from battery positive terminal and engine lifting lug into cabin with digital multimeter.
12.46 Battery without anything turned on since 11:00pm last night - 10 hours.
12.26 headlights highbeam on
12.24 ignition on.
8.91 Crank to start - difficult to read the fast changing multimeter display.
14.42 engine idling for a minute
13.4 immediately after engine turned off.
12.38 with headlight high beam on
11.94 after headlight high beam on for two minutes
8.3 to 9.6 during cranking, after several engine crank, start, stop cycles
14.38 engine idling.

The battery was replaced on 12 Feb 2018 with 466 Silver Calcium $245. Thats only 3 years 2 months ago.
 
So. Without a logical reason why, I decided to perform a mobile forced FAP regeneration this afternoon. Took 10 minutes, and was successful.
Drove back home. Stopped in the driveway engine still idling. Using Diagbox reviewed all of the live readings for fuel system, air intake system and FAP system. All of the parameters seemed to be within the expected bands of normal, and putting the Auto into stall to load up the engine the obvious parameters seemed to move in the correct directions. No obvious alerts. But several additional codes for transmission, Traction control, radio, LCD screen. Still unable to delete them.
Stopped engine.
Restarted engine, and noticed that the Depolution Fault alert and the Engine Icon did not reappear, as they usually have been since Fridays initial display alert. That's odd, as the codes are all still there including several additional codes.
Engine off again, wait, restart, drive around (urban) block, no Depolution Fault or Engine icon.
The engine seems to perform as per usual.

All I have done is perform a forced FAP regeneration cycle, Codes are still latent, but Depolution Fault and Engine Icon no longer display. I don't understand why this has occurred.

Based on above battery voltage tests particularly the voltage reducing with only the headlights on, I was becoming suspicious of the Battery.

I would be pleased to receive some comments from members that have more hands on experience with the vehicle than I do.
 
Hi.

Now a few weeks later I've had an opportunity to return the 308 to the supplier (they only sell batteries) of the battery to get it tested. Here is my paraphrase of their response:
  1. The battery only has a "service charge" as it has just been running.
  2. The alternator cannot fully charge a battery.
  3. The battery needs charging by a mains powered charger to "fully recharge" it.
So I've had the car on a mains powered Repco RBC25SS3 12V battery charger from 11:00AM this morning. The maximum output can only be 2.5Amp. After only 6 hours the battery charger displayed "Full". If, according to the battery supplier, the battery was in a state of discharge, I would have expected a 2.5A charger would need much longer than 6 hours to achieve "full" status.

So I have now connected a different older style Arlec 4Amp mains charger onto the battery. With my multimeter in series with with the charger it was only delivering 0.9A into the battery. This would tell me that the starter battery is fully charged. But I will leave it connected overnight, and see what the input current is and the voltage of the battery is in the morning.

This is now the third time people at the battery supplier have stated that alternators cannot maintain starter batteries in a fully charged condition. This is different to what I had been taught in my apprenticeship and trade days, many years ago. If this was the case all cars would need to be connected to mains chargers at frequent intervals and its self evident this is not occurring in the general motoring world.

As this is a 2008, T7 308, 2Lt HDi Auto, one cannot leave accessories on for long as the BSI shuts down the feed after 30 minutes. My daughter does not leave things turned on anyway. So how would a battery become to be in a "discharged" state? This car used to get regular weekly trips from Ballarat to Melbourne & return, but for the past several months it is mostly driven around Ballarat. I have not looked up the output amperage from the alternator but I would assume it was sized for the vehicle and accessories fitted.

I raised the question of alternator charging in an earlier post in this forum, and it was well discussed: https://www.aussiefrogs.com/forum/i...dition-measuring-and-charging-systems.120979/ In that episode the battery was damaged as the headlights had been left on overnight, and a replacement battery resolved the issue.

The whole purpose of this battery testing exercise was to hopefully rule out the battery as the cause of the many fault codes, that caused the De Pollution fault to display and the vehicle to go into limp home mode, that caused my daughter to lose confidence driving the vehicle. I'm not sure I have advanced the cause much at all.

Regards.
Whippet.
 
Last edited:
HI.

On charger overnight. Battery voltage while the charger was still connected was 15.5V, and was charging at 0.45A. Remove charger.
Start engine, battery voltage is 14.44V, with headlights on high 14.36V. So I am consider the alternator is functioning correctly.

Engine off and allowed to settle for 20 minutes and voltage is 12.6V, with headlights on high after 30 seconds 12.05V.

Headlights on high should add (4 x 55W) / 12V = 18.3Amps load onto the battery.

From a fully charged battery yesterday and overnight, I think that dropping from 12.6V to 12.05V with headlights on indicates a degraded battery. I suspect that this is the cause of the seemingly spurious fault codes. As mentioned previously the battery is 3Yrs and 3 Mths old.

I will purchase a new battery next weekend.

PS: The battery place would not test the battery in situ as they couldn't access the negative battery terminal. I suggested that they use the engine as earth, but they didn't want to do this. Its a bit fiddly to remove the battery, so I took the recharge from mains battery charger option to see what resulted. The owner of the business is really good. But I felt a bit fobbed off by the staff that served me.
 
"service charge" should be "surface charge". This is residual charge from the battery being charged before the test. In this case from the engine being stopped just before the test.
Normally you would turn the headlights on for a minute or so and retest. It doesn't sound like they know how to use a battery tester if that's all the information they can give you.

I agree with your assessment of the battery. Those voltages while not terrible, are on the low side, and would suggest the battery is on its last legs.
 
Hi.

So finally got the time to replace the battery on Saturday. I purchased a 660CCA battery during the week and fitted it myself.

Of interest all of the 13+ fault codes are now gone, except P1351 Preheating relay circuit, and P2777 sequential signal or sensor, neither appear to affect anything. Lets see if any new codes emerge after a few weeks of use.

I am embarrassed to report that on the negative battery terminal, the one under the plastic cover that itself is under the bottom of the windscreen, and hence impossible to sight unless you remove the battery, after you first remove the air cleaner upper chamber, there was an amount of corrosion. So hot water with Bi Carb soda and rinse soon removed all of the crud. I have noticed over the years that sealed cell batteries tend to not corrode terminals much. My daughters 308 was the self evident exception in this case.

Notwithstanding the amount of corrosion the actual electrical contact between the negative terminal post and the earth clamp still seemed to have 70% of clean contact area. So I still consider that the battery capacity/condition has been the cause of the spurious fault codes. I am still disappointed as this was a large high capacity "premium battery" that was only 3 years, 3 months old.

I still have the replaced battery, it will be handy for a 12V power supply for various testing etc.

I think I might shout myself a Ctek MSX 3.8 charger, for general use, as I am sick of borrowing. My old charger is still out at the farm so easier to get another for my home location.
 

Attachments

  • corrosion - earth.jpg
    corrosion - earth.jpg
    387.5 KB · Views: 123
  • corrosion - terminal.jpg
    corrosion - terminal.jpg
    770.1 KB · Views: 124
You must log in or register to reply here.
Top