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Low air flow problem

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321dave   
Thu Nov 17 2016, 09:27am
Joined: Sep 09 2011
Member No: #614
Location: Dublin
gmerry wrote ...

Hi Phil, my "concern" over the oil leaking is down to the visible drip I occasionally get on my driveway but more importantly, the possibility that the excessive oil in the vacuum pump (if I'm correct) might make its way to the brake booster (and that does create some very serious problems).

regards
G


Hi G, I'm going to fit the new intercooler pipe in a week or so, I'm thinking best put the car of the road for the whole week and finally tackle the glow plugs as well as a few other jobs.

In doing the glow plugs, I will need to remove nearly everything in the way, top of the engine anyway, funny you mention the vacuum pump as well, I'm fitting the swirl valve kit I bough thanks to Vaho, so I might as well check the pump then. It has a seal I believe where it attaches to the rear of the engine near the bulk head. I'm aware of the pump and its effect on the brake booster, and the swirl valves or as the Land Rover people refer to them as port deactivation/activation valves, but your thinking oil is being sucked in and moving along to the intercooler and up around to the intake side? I was thinking the seals on the turbo weren't the best and maybe oil was now passing on to the intercooler that way? But just as Phil mentions it's not abnormal to have a bit of oil in the intercooler and pipes from what I've read. Mind, I have more than a little bit or so it seems.


vaho   
Thu Nov 17 2016, 10:24am
Joined: Jun 25 2015
Member No: #2228
Location: Tallinn
As far as I know the vacuum pump is not connected to the inlet air pipes. There are two ways how oil can get to these pipes - through leaking turbo seals and through engine breather valve. The latter is possible because the suction pipe (No 2) of the breather valve is directly connected to the rear air inlet tube before turbo. This pipe runs below the vacuum pump so it can be confusing and can be thought to come from vacuum pump when in fact it is not.



gmerry   
Thu Nov 17 2016, 12:08pm
Joined: Dec 11 2009
Member No: #21
Location: Scotland
Hi Vaho, you are almost certainly correct! Yes, it must be the air breather pipe coming from the crankcase ventilation (which makes more sense)

I'm going to try and have another look at that pipe by the bottom of the vacuum pump.

regards
G
vaho   
Thu Nov 17 2016, 12:49pm
Joined: Jun 25 2015
Member No: #2228
Location: Tallinn
Yes, the pipe that connects to the turbocharger air pipe is most certainly the pipe no 2 and that is coming from the breather valve. Vacuum pump pipe connectors are both on the top.




vaho   
Thu Nov 17 2016, 01:29pm
Joined: Jun 25 2015
Member No: #2228
Location: Tallinn
I also think that some oil in the inlet tubes and intercooler is inevitable. As long as the oil consumption does not exceed the amount described in the user manual we should be ok. If one wants to prevent the oil fumes entering the inlet it is possible to install a separate device, like this:
http://www.ebay.com/itm/Air-Oil-Separator-Mod-Car-Truck-Engine-Intake-Clean-Clear-PCV-MPG-FJ80-Auto-FJ80-/272452671237
321dave   
Wed Nov 23 2016, 03:58pm
Joined: Sep 09 2011
Member No: #614
Location: Dublin
I'm just wondering if the vacuum pump at the rear of the engine wasn't working well or was intermittent at best what would the symptoms be to the engine and brakes etc? The C6 behaved perfectly today and not so good yesterday? Sometimes when I brake the car would travel a little on the suspension, like it was moving after the car had stopped. But today the brakes seemed tighter and stronger, and when I braked the car didn't seem to move at all after the braking stopped? It's hard to explain, but we can feel this. Acceleration seemed revier engine wise! I'm just wondering how important to the system is the vacuum pump?
vaho   
Thu Nov 24 2016, 06:57am
Joined: Jun 25 2015
Member No: #2228
Location: Tallinn
Vacuum pump provides vacuum to brakes, SWIRL control and engine pads. I think if the pump isn´t working like it suppose to, the first thing you notice is the brakes/pedal beeing very hard and then the engine vibration, especially when idling. It certainly was the case with my Volvo S80 with similar system.
321dave   
Thu Nov 24 2016, 11:04am
Joined: Sep 09 2011
Member No: #614
Location: Dublin
vaho wrote ...

Vacuum pump provides vacuum to brakes, SWIRL control and engine pads. I think if the pump isn´t working like it suppose to, the first thing you notice is the brakes/pedal beeing very hard and then the engine vibration, especially when idling. It certainly was the case with my Volvo S80 with similar system.


Thanks Vaho, I'm guessing after 130000mls there must be other slow leaks from the system now, like I'm going to see very soon with the swirl valves. Have mine bought and ready to change over next weekend (pictures coming soon).

If I wanted to check the crankcase vent as well did you purchase new seals or just reinstalled the oil trap back on the engine block? And while I'm in and around that area maybe a look down at that breather pipe you and G were referring to? No2 on the diagram above.

I'm going to see also if the rear engine mount (assuming I can get to it) is holding much of a vacuum now! I believe that mount is controlled by engine speed and the other three or idir gel or rubber mounts. So I'm going to look at those also and see if they are working correctly. Very busy car repair weekend and most likely evenings next week.
vaho   
Thu Nov 24 2016, 02:09pm
Joined: Jun 25 2015
Member No: #2228
Location: Tallinn
If the SWIRL actuators are leaking it doesn´t affect much of the other systems because there is no constant vacuum to the actuators. More so, I think the vacuum pump has such a capacity that if you even disconnect one hose somewhere, you still have vacuum left for brakes and mounts.

The crankcase vent needs no new seals. The excisting ones are perfectly reusable. There are two plastic ones which didn´t move at all and one rubber one which came a little bit loose. Just push it back before pushing the vent back. I opened the vent also to see what is inside and there is only one rubber membrane and a spring, nothing else, just empty space so there is not much to look for.
321dave   
Thu Nov 24 2016, 03:17pm
Joined: Sep 09 2011
Member No: #614
Location: Dublin
Hi Vaho,
thanks for the advice about the vent seals. Did you have a look at the breather pipe? Im wondering about the oil and where it might be coming from.
vaho   
Thu Nov 24 2016, 05:23pm
Joined: Jun 25 2015
Member No: #2228
Location: Tallinn
The pipe just connects the crankcase vent and rear turbo inlet hose. It s not much to look other than cracks. If you lift the vent assembly out you get no access to the pipe also, there is a metal two-tube assembly before the rubber pipe and the pipe connects to that. You see when the vent assembly is out.
Crankcase vent assembly itself was oily inside but this is ok because it is the crankcase ventilation system, most of the oil goes back to the sump but some oil vapours are sucked into the air inlet system.
cruiserphil   
Thu Jan 26 2017, 08:59pm

Joined: Jan 24 2010
Member No: #38
Location: Celbridge
Lads,

I had reason to remove the intercooler pipe on the 2.7 during the week to give me access to replace a leaking hydraulic pipe. When refitting the assembly, I found great difficulty in getting the butterfly box to insert correctly into the seal in the top of the intercooler pipe. The seal is in good condition but I found it tended to get dragged down into the intercooler pipe when inserting the butterfly housing, compromising the sealing. It took numerous attempts to finally get it right.

So, if your doing this reassembly, look carefully when you insert the butterfly box into the intercooler pipe and ensure you can see the complete seal face contacting with the flange on the butterfly box before tightening the circliip

Best regards,

Phil C.
321dave   
Mon Jan 30 2017, 12:44pm
Joined: Sep 09 2011
Member No: #614
Location: Dublin
Hi Phil, I know about that problem as well, just to update on my new pipe, I also purchase new seals and the part that attaches back into the throttle body itself, I guess it's a kind of right angle connection between the two. All been great since the new parts and seal went back in around Christmas. No sign of an oil leak as well with new pipe and the seal your referring to which comes at the top of the new pipe only(pity).
C6Dave   
Sat Oct 05 2019, 01:52pm

Joined: Oct 01 2009
Member No: #1
Location: Northumberland
gmerry wrote ...

.... the air flow meters are attached to the big air filter housing (True left hand side of the engine by viewed from the drivers seat facing forwards). One air meter is on the hose going to the rear turbo: the other is on the hose going to the front turbo (towards the radiator).

Its worth swopping the two air flow meters (the front one goes into the rear berth and the rear goes into the front berth). If the fault remains the same, and doesn't follow the swopped air flow meter, you know its not a meter problem.

Beyond this simple and easy job, you need access to Lexia/Diagbox to see actual live airflow values and how the EGR valves / Butterfly valves are responding to the ECU commands. Don't diagnose any problems just with the fault codes.

Also as Phil says, unlikely to be an airflow meter

So after my radiator and water inlet tank change I now have a P0104 & P010F error so swapped the MAFS over as above but for some reason in Diagbox I can't clear the fault codes to see what happens. ATM with them swapped the fault still points to the rear MAF but a rest may clear it?





Now they had the front of the car to pieces and I did find 1 air hose clamp not tightened properly and I suspect that there may be another lower down but it needs the undertray off to get to it, so will be taking the car back to them to check.

EGR's are 'supposedly' 'mapped' out so not suspecting it to be one of them

BTW no MIL light on the dash either, just the error in Diagbox and a bit of 'rough' idle.
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C6Dave   
Tue Oct 08 2019, 02:35pm

Joined: Oct 01 2009
Member No: #1
Location: Northumberland
Swapping the MAF units did nothing and as suspected the error remained at the rear sensor which when I went to remove it, the jubilee clip hadn't been tightened fully.

Left them swapped and made sure all the hose clips were secured.

Managed to reset the error codes yesterday after I switched the wifi off on the laptop and rebooted it (Diagbox wanted to contact Citroen )

Gave the car a run today and re checked for errors and all I have now is a P1536 (Permanent error) so ordered a new Brake Pedal Switch from Eurocarcare (don't tell my wife but she probably caused that with her feet on the France road trip )

Fitting is quite straightforward: - Click Here -
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