I have just changed my oil today (strangely only 3.75 litres including oil filter came out, 4.25 went in - go figure)
This involved removing undertray.
I was friggin faberglasted at the tortuous route the air intake tubing takes - feck knows why people mess around with air filters, I doubt it makes any difference whatsoever to air flow.
The route - small rectangle hole both sides above radiator (nice-warm air-lovely, just what you want for efficient combustion, not ), several sharp 90 degree bends into air filter, 90 degree bend out of air filter, across to back of engine, 90 degree bend, across engine again 90 deg bend down to turbo over exhaust (more warm air), thru turbo down to undertray, 90 deg bend, 120 deg bend, S curve then forwards to front of engine, 90 deg bend thru what I assume is intercooler infront of rad, 90 deg bend out, again across other side of engine front, 90 bend up front of engine, thru EGR which is approx a 70% restriction and eventually into inlet manifold! I'm surprised any air ever actually reaches the turbo, let alone the engine.
What worried me (on a 27k) engine is that the ally pipe from exhaust to egr valve was already well sooted up. (its coming off this weekend for a clean and blanking plate). Also there was a significant amount of oil seeping from the joints of the air inlet on the way in and out of the intercooler. 4 joints in all. The oil must come from the crankcase ventilation. If its seeping out of the joints (x4) then there must one heck of a lot of turbo pressured air leaking out too, when it could be providing more boost to engine. Would be interesting to measure the pressure drop across the pipe system. why aren't these jubilee clipped instead of unsupported flimsy rubber o ring seals?
This involved removing undertray.
I was friggin faberglasted at the tortuous route the air intake tubing takes - feck knows why people mess around with air filters, I doubt it makes any difference whatsoever to air flow.
The route - small rectangle hole both sides above radiator (nice-warm air-lovely, just what you want for efficient combustion, not ), several sharp 90 degree bends into air filter, 90 degree bend out of air filter, across to back of engine, 90 degree bend, across engine again 90 deg bend down to turbo over exhaust (more warm air), thru turbo down to undertray, 90 deg bend, 120 deg bend, S curve then forwards to front of engine, 90 deg bend thru what I assume is intercooler infront of rad, 90 deg bend out, again across other side of engine front, 90 bend up front of engine, thru EGR which is approx a 70% restriction and eventually into inlet manifold! I'm surprised any air ever actually reaches the turbo, let alone the engine.
What worried me (on a 27k) engine is that the ally pipe from exhaust to egr valve was already well sooted up. (its coming off this weekend for a clean and blanking plate). Also there was a significant amount of oil seeping from the joints of the air inlet on the way in and out of the intercooler. 4 joints in all. The oil must come from the crankcase ventilation. If its seeping out of the joints (x4) then there must one heck of a lot of turbo pressured air leaking out too, when it could be providing more boost to engine. Would be interesting to measure the pressure drop across the pipe system. why aren't these jubilee clipped instead of unsupported flimsy rubber o ring seals?