Check yourself for losing your hearing and halucinating. That highway engine noise in a 240d can hammer your brain. I have a couple of them but do not drive them that often. I have little brain material left to spare.

These engines running better in cooler ambient temperature needs understanding. Cold air of course is denser but in theory should reduce the combustion process a little.Not enhance it.

The effect may reduce milage a little by changing the burn rate. With all the gas cars out there going direct injection there may be hope yet that someone out there will makea a 240d a direct injection engine.

Soon enough the required parts should turn up in junkyards. Getting some sensors mounted on these blocks may be the challenge. Someone is going to try it at some point.

Injecting in the area of the present precombustion chamber area with the actual prechamber insert out of the block may not be the most efficient introduction point but it should help. On the otherhand it may be an impossible point to direct injection from is more likely. Indirect injection like these engines employ is not all that efficient to put it mildly.