Glow Plug error diagnosis.
 

Couple of weeks ago i got 4A4E glow plug error code on my 2009 X5 35D. Today i finally took the intake out.

Thanks sgrice for the write up and pics and it was really helpful!! The hardest part was undoing swirl motor electrical connection and egr temp sensor electrical connector.Like you i decided to take the throttle body out along with the intake.

Then i checked the resistance of all 6 glow plugs and all are showing around .4~.5 Ω.So to me it looks like glow plugs are fine and its the controller.I also tried to run rheingold test plan for the glow plug error code and it was saying that resistance values are not available for ceramic glow plugs.It was suggesting to change all 6 glow plugs and if error shows up again then change the glow plug controller.Its really strange that resistance values are not available??That's what rheingold was showing??Does it mean that checking the condition of ceramic glow plug by measuring its resistance is not a proper way?? I think glow plug controller is covered by CPO as my brochure says ' all control modules'. So at this point i am kind of stuck.what to do now?If i can somehow make sure that glow plugs are fine then i can take my car confidently to the dealer for repair under CPO.Suggestions please!!

Here are the pictures of my intake after 91000 kms.Round ports are showing signs of CBU just like sgrice's car and rectangular ports are absolutely clean with a very light film of oil.

Nice work! Sounds to me like the glow plug control module, but I am also unsure if your glow plug test method is totally correct. Hopefully ZetaTre will chime in, as he seems to really know a lot of technical details.

Interesting that your pics look so similar to mine. How many miles on your car? [Edit - sorry, I didn't see where you stated 91000 km in your original post] I don't want to hijack the thread away from glow plugs, but how do the swirl flaps look? My prediction: they (and the intake manifold) are soaking in a nice hot degreaser bath as we speak!

I never posted pics of my EGR valve, but it also had a fair amount of CBU on it. Very easy to clean, though.

Glad the write up was helpful.

Sorry I can't be more helpful about the glow plug testing method.

Regards.

Car is 2009, has 91000 Kms and here are more pics of intake manifold ports.quite a bit of carbon on the manifold side but engine side is clean.Throttle body is looking clean because it was replaced around 15000 kms ago.

Yes i am not sure either if checking plugs by resistance is the right way.But all of my plugs are measuring same resistance value of .5 ohms.

I haven't soaked the parts in degreaser yet.:). was too late last night. will be doing it tonight.

Does anybody know how M57's cylinders are numbered?I am thinking to only change the plug with a error.My code was according to rheingold "4A4E:glow plug,cylinder 3,activation,Fault type-open circuit." So is it going to be number 3 from the front?

re: numbering of M57 cylinders - This link doesn't address the M57 specifically, but it seems that every other bmw engine going from 1 to 4/6 cylinders starts with 1 in the front. So I would think third from the front is highly likely.

FWIW, this link covers a ton of info about the m57 engine. You may already know a lot of this stuff, but it's nice to have it in one spot. I did search it for cylinder numbering, but couldn't find that specific issue addressed (did find that the firing order is 1-5-3-6-2-4, FWIW).

Hope that helps.

I'd say use the coil trick...

In other words: I think your code is for a specific glow plug. So take the one adjacent and swap it. If the code moved to a different cylinder then it's the glow plug. If it doesn't is the module or the harness

Thanks sgrice for the links!!
After reading the attached document last night, I found that 3 Volts should be safe for the plugs to test current draw and decided to feed the glow plugs 3V for 2-3 secs from my power supply (variable current and volt power supply i use for hobby projects).And i found that all plugs were showing same current draw of something 5.3 AMPS at 2.7~3 volts and now i am thinking its the bad glow plug controller.After cleaning, i am going to put everything back and will take to the dealer.I am waiting for the various gaskets and thermostat that i ordered from
BMW of Morristown.Its gonna be few days.

I thought about it but my battery negative is removed.Just worried about any damage by reconnecting the battery as lots of electrical connectors are removed.

Sorry i didn't get it first.I thought you were saying swapping the electrical plug. Yes that a smart idea to physically swap the glow plug.But to that i will have to put everything back and start the engine and warm it up for glow plug extraction.So i will just take it to the dealer for glow plug controller problem and hopefully the controller will be covered by CPO.

Not necessary: having direct injection it will fire up without the intake.

Just swap the glow plugs and fire up the engine. You will get all sorts of codes, but all you care about is the one for the glow plug.

When my dad's glow plugs were shot, the code came right back after a few minutes from startup

Erase all codes, fire up the engine (it will be loud if, particularly if you don't plug the EGR cooler) and see if the glow plug code comes back.

Yes sure will try to do that:thumbup: