Glow plugs E53 Diesel 2004 mod
 

When I read the error codes, I get the following errors on the glow plugs, but the car starts very easily (not so cold 2-3 degrees) should I replace them anyway when I have the car at the workshop or there may be other mistakes that make this error message is coming?

We found we had all 6 glow plugs failed. It still started fine but we replaced them anyway as part of our maintenance.

Also found that the EGR valve had a lot of carbon build up so cleaned it, put a new filter in and it ran WAAAYY smoother and gained power and economy back.

It may be that the glow plug module has failed (as well). The LCI cars (2004 - ) use a solid state glow plug controller (relay) that is known the have internal wiring failures.

I am about to replace all six glow plugs AND the controller (while I'm in there, I'll do it once).

https://i.ebayimg.com/00/s/MTIwNVgxN...B/$_57.JPG?561

https://www.ebay.com/itm/FOR-BMW-X3-...72.m2749.l2649

Thank you for your reply, it's quite expensive to exchange these in Norway $ 860 so I would rather not exchange them if it is not necessary :)

The glow plugs are used for more than just cold starts - they are also activated when the engine is under light loads, to maintain cylinder temperatures. This helps the engine run cleaner and smoother. It's also important for emissions.

Several owners have commented about smoother running after glow plug changes (like LVR above).

Your fault could just be faulty glow plugs or it could be just a faulty controller. Problem is, you need to remove the intake manifold to change either, hence most people just change all six glow plugs and the controller. If you have the time to remove the intake manifold multiple times, you could locate the faulty components but as glow plugs really need to be changed at about 100,000 miles it's likely you'll want to change them all out anyway. If you still register faults after changing the glow plugs, then you need to change the controller.

Or just do it all at once. ;)