High crank case pressure / oil leak - now limp mode F48 2.0D
Discussion
Hi, This seems like a good forum to ask about my issues at the moment. I've been roped into looking at a friends car that has a bad oil leak.
A couple of months ago we removed the valve cover as the leak seemed to be coming from that area, this involved removing the injectors and any sensors that were in the way. when we put it back together it ran fine although didn't solve the oil leak.
Fast forward to this weekend and I've had another look and the oil is coming out of the filler cap, quite badly, I fitted a new cap and even used 2 rubber rings (one of the old cap), it goes on really tight but oil is still passing it, I cant see any cracks or anything in it and the leak is defenately coming from under the cap.
The next step was to remove the valve cover again and check the PCV valve which all seemed to be working ok so I suspect its a ring or bore problem, the car has done 170k. But when I put it all back together, after being super careful with the injectors etc it won't run properly. It says drivetrain fault and the engine light is on, it also misses slightly when revved and wont go above 2500-3000. I've cracked the injectors to get rid of any air and if you unplug them the engine note changes on each injector so they are working.
I've had my code reader on it (icarsoft V3 BMW) and when I cleared all the codes the engine light did actually go out and the engine revved freely and sweetly foir about 5 seconds until the light came back on so its not an injector/fuel problem.
The problem now though is my code reader is saying there aren't any codes present and that the engine management light is off when its quite clearly on. One of the faults I cleared was for the DPF saying its nearing the end of its life and when I do a pressure check on it its reporting 500hpa before the DPF but I'm a bit skeptical that my reader is reporting correctly, 500 seems a nice round figure and doesn't seem to change hen you rev it. I'm now at a dead end with it.
A couple of months ago we removed the valve cover as the leak seemed to be coming from that area, this involved removing the injectors and any sensors that were in the way. when we put it back together it ran fine although didn't solve the oil leak.
Fast forward to this weekend and I've had another look and the oil is coming out of the filler cap, quite badly, I fitted a new cap and even used 2 rubber rings (one of the old cap), it goes on really tight but oil is still passing it, I cant see any cracks or anything in it and the leak is defenately coming from under the cap.
The next step was to remove the valve cover again and check the PCV valve which all seemed to be working ok so I suspect its a ring or bore problem, the car has done 170k. But when I put it all back together, after being super careful with the injectors etc it won't run properly. It says drivetrain fault and the engine light is on, it also misses slightly when revved and wont go above 2500-3000. I've cracked the injectors to get rid of any air and if you unplug them the engine note changes on each injector so they are working.
I've had my code reader on it (icarsoft V3 BMW) and when I cleared all the codes the engine light did actually go out and the engine revved freely and sweetly foir about 5 seconds until the light came back on so its not an injector/fuel problem.
The problem now though is my code reader is saying there aren't any codes present and that the engine management light is off when its quite clearly on. One of the faults I cleared was for the DPF saying its nearing the end of its life and when I do a pressure check on it its reporting 500hpa before the DPF but I'm a bit skeptical that my reader is reporting correctly, 500 seems a nice round figure and doesn't seem to change hen you rev it. I'm now at a dead end with it.
Difficult to comment on the crankcase pressure issue as you ve checked what I would have, however with regards to the injector issue. I got caught out once by coded injectors. They have to be in the original location.
I mixed mine up and had injector knock (not the same vehicle as yours) something worth checking out.
I wiped the codes using a code reader, and re entered them in the correct order, each injector had a 10 digit code.
ETA, if the crankcase pressure is that high due to bore wear/ broken ring is similar I’d think it would be smoking pretty badly. Ideally you should do a compression test. Check everything in the PCV circuit. Sounds like classic blocked filter or stuck check valve to me, possibly a soft, collapsed hose.
I mixed mine up and had injector knock (not the same vehicle as yours) something worth checking out.
I wiped the codes using a code reader, and re entered them in the correct order, each injector had a 10 digit code.
ETA, if the crankcase pressure is that high due to bore wear/ broken ring is similar I’d think it would be smoking pretty badly. Ideally you should do a compression test. Check everything in the PCV circuit. Sounds like classic blocked filter or stuck check valve to me, possibly a soft, collapsed hose.
Edited by Ritchie335is on Monday 21st July 11:01
There isn't much to the PCV valve really, its built into the valve cover, there is a plastic cap on top which holds a diagphram down which has a spring under it, then its a short flexi pipe to the inlet right near the turbo. from what I can see the diagphram is held open normally by the spring and it must only get sucked closed when the turbo is on boost, otherwise its a straight passage between the valve cover and inlet manifold.
I don't think the DPF has a problem either, I've just done a other reading and this is what it throws up,
Exhaust gas pressure before the DPF 500hpa, exhaust gas pressure before exhaust turbo 1035hpa, those figures don't change when you rev it but the actual differential pressure is only 1.97hpa at idle and increases slightly if revved
I just don't understand why the hpa before the dpf is steady at 500, the one below at 1035 stays static as well, only the differential pressure goes up slightly as you rev it.
But the main issue that I can replicate now is if I disconnect the airflow meter it shows a fault on my reader, if I clear that fault the engine light goes out, the car revs freely and then the engine light comes on again and its back to running rough, if I then plug the airflow back in my reader doesn't show any faults, so how is it clearing a fault briefly it doesn't know about. I hate modern cars.
I don't think the DPF has a problem either, I've just done a other reading and this is what it throws up,
Exhaust gas pressure before the DPF 500hpa, exhaust gas pressure before exhaust turbo 1035hpa, those figures don't change when you rev it but the actual differential pressure is only 1.97hpa at idle and increases slightly if revved
I just don't understand why the hpa before the dpf is steady at 500, the one below at 1035 stays static as well, only the differential pressure goes up slightly as you rev it.
But the main issue that I can replicate now is if I disconnect the airflow meter it shows a fault on my reader, if I clear that fault the engine light goes out, the car revs freely and then the engine light comes on again and its back to running rough, if I then plug the airflow back in my reader doesn't show any faults, so how is it clearing a fault briefly it doesn't know about. I hate modern cars.
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