Possible head gasket failure

[X5Sport]

I’m glad that between us we managed to come up with a useful answer. As said, these engines just don’t suffer head gasket issues unless seriously abused. With a leak of that magnitude I would have expected a hydraulic lock condition if it had failed so it made sense for it to the somewhere upstream (no pun intended) with the water being spread across all cylinders. Of course in days of yore, a bit of water injection was good for power - that maybe not that much at once though .

My dad was a victim of “it’s your head gasket sir” many years ago with a brand new Audi. It was actually a loose radiator bottom hose clip that allowed the coolant to be dumped along the M3. The car was less than a week old and hadn’t been properly PDI’d. The AA missed the detached hose completely!

Happy the pics helped you both as well.

[StuBeeDoo]

Glad you've found the source of the problem.

Long term I've said to blank off the gas going into the EGR and code it out, then remove the EGR thermo and cooler altogether.

I had an E46 330d. Blanking the EGR, deleting the swirl flaps, and cleaning the inlet runners and ports was the best thing I ever did to it. Made it more economical, too.

[Alchemist]

Yeah likewise, I had the same car (late E46 330D manual - loved that car). Did the same: swirl flaps, EGR blanked and remap to 256bhp all in one hit. Cleaned the hard baked black gunk from the inlet too when I had it on the bench.

I've suggested my dad does the same to the X5, and removes the EGR cooler entirely as it can be bypassed.

[X5Sport]

What impact does deleting the EGR have on cars equipped with a DPF as that effectively forces all soot straight to the exhaust side with no ‘reburn’ in the engine? Just curious as the current system is supposed (allegedly) to make the exhaust particle emissions lower and not dump it all into the DPF to handle.