[andramont726]

This past weekend my friend's 2006 E90 325i overheated during a trip (at highway speed). The friend reported power was cut as the overheat sign was displayed on the dashboard. As big of a spaz as he is, he didn't immediately pull over, but kept driving for a few miles to the nearest gas station.

Needless to say, the car was a full gallon+ short.

I can't spot any leaks under the car, anywhere, so i'm going to chalk this one up to bad maintenance or fluke.

That being bad alone, now there are a bunch of issues which I found while diagnosing the overheat. Though I can't say they're caused by the overheating it's hard to pretend they'd have hid this long.

At wide open throttle acceleration from a stand still, when the car goes between 2nd and 3rd gear the car suddenly looses a ton of power, and a TON of white smoke is released at the same time the CEL is lit. INPA tells me it's P0139 and P0159 error codes, with an accompanying message that it happened due to the ecu requesting power cut but the O2 sensor kept showing combustion. I can reset the error and they stay off until the next high power gear change.

Now here's the kicker... on my way back home just now from doing this run, at roughtly 4k rpm (3/4 throttle) up a hill the CEL lit up again, but this time there were 2 different errors, something about electric pump rpm mismatch and cyl 3 misfire (engine was jerking slightly at this point). I again reset the errors and car immediately resumed smooth cruising...