After heavy rain I noticed the rear passenger foot well in the E30 is full of water. Can't see any signs of water ingress through the door seals or any stains in the headlining, but am told a common cause of this is the windscreen-cowl, so will be looking into this soon. For now, I have drilled a nice drain hole so at least it won't be filling up again.
More bad news for the 5 Series I'm afraid. Got it up on the ramps at work with five mechanics and as many torches to finally see where the bulk of the oil is coming from. In this post [http://beemerlab.blogspot.co.uk/2014/07/e60-bad-oil-leak-was-it-running-too.html?m=0] my attention was solidly on the turbo oil-feed and return pipes, but further investigation has revealed that no oil is dripping from them and if they are leaking then it is only a seep, which is eventually building up on the underneath of the pipes. The main oil leak it would seem is running down the front of the engine. Unable to see where though or trace where the oil is running from due to the belts and pulleys covering the front of the block so well, I tentatively assumed it was coming from the front main crank-seal - oh dear. It stands to reason that swirl-flap damage could have unbalanced the crank somewhat and caused the front main-seal to leak, but this theory is stopped by two factors - 1. If oil was leaking so badly from the front crank-seal, it would be hitting the pulley and have the trademark 'spray pattern' in a circle around the main-pulley, and 2. If swirl-flap damage had unbalanced the crank enough to let this much oil out, then the engine would be a bit more recalcitrant that is being!
Pressurised oil?
So where is the oil coming from? We blasted the entire front of engine with brake-cleaner and stood back to watch where the oil arrived from. Thankfully we watched it pool and run down from above the main-pulley. The other lads suggested the usual suspects - rocker-cover gasket or a loose oil-way at the front of the block, but there is no denying signs of fresh oil are present everywhere on the engine where there is a gasket or seal. This means the oil is being forced out of these joints somehow by pressure building up in the crankcase and would explain how oil that cannot be from the frontal leak has made its way onto things that are nowhere near it, i.e the turbo feed/return pipes. It also explains my other big problem - oil entering the air-inlet. The worst case scenario is the main turbo-seal dumping oil right inside it. This makes for both a lot of oil getting blown into the engine, but also gives a smoke-machine effect out the back, the latter of which I have no signs of as yet.
Smoky CCV [Crankcase-Ventilator]?
I removed the rubber-hose that recirculates the CCV (crankcase-vent) back into the turbo while the engine was warm and running. Thick oily smoke was billowing out of the CCV, which I duly replaced [eBay £35], though it did not affect the problem and holding a hand in front of the smoking pipe for a minute leaves an oily residue. It would appear the oil is getting into the air-inlet by condensing down the CCV recirc pipe into the turbo impeller. This is definitely not normal CCV behaviour and finally gives a sure sign off abnormal crankcase pressure. Finally, with the car on ramps and the underbody-protection fully off it became clear that oil was dripping pretty bad from the back of the engine and pretty much everywhere else, even the sump.
Verdict:
I started another thread on BMW Land [http://www.bmwland.co.uk/forums/viewtopic.php?f=5&t=163497] and the torrent of 'I told you so' replies came in and backed up my fears about piston 6. The rings are stuck inside the piston and not making good compression. The lack of power isn't really being picked up under normal driving, but the blow-by is so bad that it's allowing combustion pressure straight into the crankcase, hence burnt oil and exhaust smoke pouring out of the CCV. You wouldn't think a swirl-flap bouncing round could cause the rings to do this, but check the picture below. Well, you live and learn. This weekend I will be stripping the sump off the car and then, of course, the head is coming back off, which means more new bolts and another new gasket, coming to about £120. Sadly, even BMW cannot tell me exactly which piston my engine has from neither my reg. or VIN, so I will have to pop it out the top of the block and identify it before ordering one as they're over £200, but this means the car is off the road at least another week. I managed 268.5 miles between engine rebuilds...
Following on from this post - E46: Inlet full of oil! Re-con time. - where I discovered the intake-manifold was full of oil, I decided to give the entire thing a good clean out. The sensors, actuator and throttle-body were removed and given a good rinse with brake-cleaner. There was still oil pooling in the manifold, so I just kept on squirting brake-cleaner down the ports and turning the manifold round to run it all back to the main plenum. The Vanos [or Valvetec, whatever] seemed to benefit the most from this as the tubes were full of oil and sticking a bit. They now slide up and down freely and hopefully the electronic-actuator will still work now its clean.
The CCV sits below the inlet-manifold in a plastic-housing, along with the main wiring-loom box. Separately it looks like the diagram. These are known as 'vortex' type breathers, as crankcase pressure is relieved from the head via tube [3] and oil is separated in a spiral and runs down tube [4] back to the sump. The air-pressure is then vented via a diaphragm through tube [2] into the throttle-body, which provides a constant vacuum that keeps the engine as a suitable idle. When the vortex is clogged with oil and rust, pressure builds up in tube [3] and backs up into the head, down into the crankcase and forces oil and air back up tube [4]. This then pushes the diaphragm back and allows the oil up tube [2] into the inlet-manifold. This is clear in my case by the wiring-connectors to the other end of tube [2] and the diff.-pressure sensor being filled up with oil past the metal prongs.
Stripped, the CCV looks like this. The diaphragm housing was completely jammed solid with oily crud, which had leaked round the whole housing. The spiral oil-seperator was clogged with oily rust, which took a lot of getting out. All items were soaked in brake-cleaner and left in the parts-basin at work, then the oil-seperator was blown through with 200psi from the airline. Eventually I got quite a lot of air-flow through the vortex and the diaphragm-housing was squeaky clean, so I threw it back together and refitted the CCV and manifold. I've saved £45 on the part and this quick-fix should work for enough time at least for me to rule the CCV out if the problem persists. If it goes and comes back, £45 is not a lot to spend and I will be glad to do so if it cures the low idle problem!
Removed the inlet-manifold to check the CCV [crankcase-ventilator], crankshaft-sensor and main wiring-loom / connections. It didn't look too bad underneath, though there are some signs of a stuck CCV valve. I put the manifold down next to the car while I was working and after 5 minutes I noticed a large pool of dirty oil had run out of the throttle-body, so I placed that end in a bowl, jammed the butterfly open and leant the manifold on its end. Another 1/4 pint of oil ran out of it and today I removed the throttle-body entirely and managed to get about half as much again. More is coming, so I've blasted carb-cleaner back through the inlet-ports and left it to run down.
So either the piston-rings are completely shot and are leaking that much oil back up into the inlet, in which case the engine wouldn't run... or it's one heck of a stuck CCV. In this case, it would appear the crankcase-vent valve has stuck closed, which is allowing pressure to build up and pump oil back through the clean side of the CCV-system, dumping it right into the top of the throttle-body! Rather than creating a vacuum in the air-inlet that keeps the car at a decent idle, the CCV is pumping combustion pressure instead and covering all the sensors with hot oil. Not good. This is the most poorly engine I've ever seen.
While the throttle-body is off I may as well give it a good clean, along with all the sensors that had filled up to the wiring-connector with the pressurised oil. Even if this doesn't completely clear the rough running faults, it has certainly given the engine a new lease of like and it never does any harm to flush everything out and eliminate any further problems in the inlet.
Well, I'm certainly glad to report that the oil gushing onto the exhaust / cat has stopped with the replacement of the blown up vac-pump and I now have good pedal feel and stoppage. Sadly, even the return of some vacuum isn't enough to cure the low-idle and rough running. I replaced the obvious things, both cam sensors and the mass-airflow meter, but this hasn't sorted it either. I'm guessing there is either a severe vacuum / vent problem, or it's going to be to g related... Oh joy!
The diagnosis will go as follows:
Remove and fully check out inlet manifold.
Thoroughly check all CCV lines and the valve.
Clean and check all electrical connections.
Test for compression.
Move on to timing.
The CCV sits below the inlet-manifold in a plastic-housing, along with the main wiring-loom box. Separately it looks like the diagram. These are known as 'vortex' type breathers, as crankcase pressure is relieved from the head via tube [3] and oil is separated in a spiral and runs down tube [4] back to the sump. The air-pressure is then vented via a diaphragm through tube [2] into the throttle-body, which provides a constant vacuum that keeps the engine as a suitable idle. When the vortex is clogged with oil and rust, pressure builds up in tube [3] and backs up into the head, down into the crankcase and forces oil and air back up tube [4]. This then pushes the diaphragm back and allows the oil up tube [2] into the inlet-manifold. This is clear in my case by the wiring-connectors to the other end of tube [2] and the diff.-pressure sensor being filled up with oil past the metal prongs.
