N42/N46 Bad Coil Symptoms & Codes & Replacement

How to diagnose and replace a bad coil on the BMW E46 with N42/N46 engine.
INPA errors on my car:
2783 CDKLM - Heissfilmluftmassenmesser
Signal unterhalb Schwelle oder Kurzschluss nach Minus
Error code: 06 27 83 62 01 01 02 01 28 73 37 1E 0B 10 00 FF
FF FF FF FF FF FF FF FF
-------------------------------------------------------------
278C CDKTA - Ansauglufttemperatur
Kurzschluss nach Plus oder Leitungsunterbrechung
Error code: 06 27 8C 62 01 01 12 01 26 73 3A 15 9E 68 FF FF
FF FF FF FF FF FF FF FF
-------------------------------------------------------------
2754 CDKDZKU1 - Ueberwachung Zuendspule 3
Kurzschluss nach Plus oder Nichtimpedanz
Error code: 06 27 54 21 21 00 00 02 1E 73 6B 43 B2 72 95 73
76 27 B1 37 95 FF FF FF
-------------------------------------------------------------
274E CDKMD - Aussetzererkennung, Summenfehler
Katschädigende Aussetzer
Error code: 06 27 4E 81 01 00 00 02 1F 73 6B 48 73 B2 38 73
76 2E 66 B2 32 FF FF FF
-------------------------------------------------------------
2743 CDKMD01 - Aussetzererkennung Zyl.3
Katschädigende Aussetzer
Testbedingungen erfuellt
Fehler bisher nicht aufgetreten
Error code: 06 27 43 81 01 00 00 02 1F 73 6B 48 73 B2 38 73
76 2E 66 B2 32 FF FF FF
-------------------------------------------------------------
2781 CDKPH - Nockenwellengeber Einlass
unplausible Phasenflankenanzahl
Error code: 05 27 81 08 05 00 00 01 27 73 88 29 73 60 7C FF
FF FF FF FF FF FF FF FF
=============================================================
Other possible INPA codes related to bad coil:
2742 Misfire Detection Cyl 1
2743 Misfire Detection Cyl 3 (4cyl) or 5 (6 cyl)
2744 Misfire Detection Cyl 4 (4cyl) or 3 (6 cyl)
2745 Misfire Detection Cyl 2 (4cyl) or 6 (6 cyl)
2746 Misfire Detection Cyl 2
2747 Misfire Detection Cyl 4
2753 Ignition Coil Cyl 1
2754 Ignition Coil Cyl 3 (4cyl) or 5 (6 cyl)
2755 Ignition Coil Cyl 4 (4cyl) or 3 (6 cyl)
2756 Ignition Coil Cyl 2 (4cyl) or 6 (6 cyl)
2757 Ignition Coil Cyl 2
2758 Ignition Coil Cyl 4
2781 Camshaft Sensor Intake
Buy Valve Spring Compressor Tool Kit for BMW N42/N46: bimmerzen.com/store
How to use the VSCT tool: • Using 3D printed tool ...
Fix oil consumption on BMW N42/N46: • BMW N42/N46 Valve Stem...
DISCLAIMER:
BimmerZen assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. Use this information at your own risk. BimmerZen recommends safe practices when working on vehicles and or with tools seen or implied in this video. Due to factors beyond the control of BimmerZen , no information contained in this video shall create any expressed or implied warranty or guarantee of any particular result. Any injury, damage, or loss that may result from improper use of these tools, equipment, or from the information contained in this video is the sole responsibility of the user and not BimmerZen.

[@CarAlex]

For a non native German speaker, you pronounce the error codes very good 👍

[@FilekGP]

Hey, thanks very much for helpful videos! I'm now sorting out a 318i, which was kind of a trade in, we were selling an E91 325i after an overhaul and got the E46 for like 500 €. There was every leak possible on the N42, and it was also starting on 3 cylinders, I didn't know what could it be, so finally I bought a compression tester, and... fourth cylinder had 5 bar, the others were 11-ish. Also lots of blue smoke after sitting in idle. So there we go, engine overhaul. I bought the STLs for the valve steam compressors, which were of huge help, as well as your videos. We have done piston rings, rod bearings, the head, head gasket, all other gasket, new CCV, new chain, guides and tensioner.. after turning it a bit without fuel pump fuse, start went great, but after warming up a bit, when pressing gas faster, it's cutting out. I think there were these errors regarding coil no. 4, I've gotta try some other coil tomorrow. Thanks for the videos! I'm able to do a lot myself, but I won't get anything done if I were to record it, so I really appreciate the work you put into these.

[@MySkullzDented]

Great video. I was on a roadtrip in my 318i and 2 coils failed at the same time🤔 Easy and cheap fix...once i finally aquired new coils after an extensive hunt, and a night in a hotel in the countryside😂

[@Karmacoming4you]

Thanks for the video. I have same error codes. Swaped the coils before watching the video and will test them again. I had yellow check engine warning before and did not come back yet....

[@Moodshroom]

thanks bro

[@jozsefmenus9811]

Thanks.

[@WayToManyAssassins]

N46 engines aren't too bad as long as they are serviced frequently, they do need new valve stems at about 100,000km but the chain can last up to 200,000 if looked after. Oil leaks need attention too

[@the_g371]

naah, it is a shitty engine, that's why we watch this video, the glory days of BMW is over. Never before with any BMW engine I had even close special effects as with this miracle.

[@TheTom7]

Hello, very cool videos, thank you for all those great informations. I have a question about those n42 engines, is there any preventive must things to do on them? I'm new on this engine, I have one good running I'll say and I want to keep it like that as much as possible, thank you! :D

[@leoomassaro]

Thanks for the excelent instructions, you deserve a lot more subscribers! I'm having a problem with my N46 E90 and I wonder if you can help me figure out whats going on... The car runs fine almost everytime, but sometimes when I start it, put the reverse in a hill and foot the gas right after the start, the engine shakes and even stops if I dont release the throttle. On the other hand, in the same scenario, if I put the car in Park first, then rev it a little bit and then put the reverse, the car goes backwards just fine. At first I thought it could be the PCV valve, but I checked and it's fine, and now I wonder if it might be a bad coil or someting else... Do you have any idea of what may be causing this issue?

[@BimmerZen]

Did you check for codes?

[@rikymalone]

Hello friend can you help me please. I have a e46 bmw 318i witch n42b20 engine and have some problems. In the morning when I start the car goes good, when gets idle on 800 rpm goes smoothly and then the engine stop, so I start the car again and present a misfir in cylinder 3 p1347 code. I changed the coil of the position and the code still in 3 cyl I changue the inyector of the position and the code still in 3 cyl I checked the spark and it’s good But I tested the signal in the third inyector pulse and it’s intermittent, when I erase the code with odb the signal goes good but in a while the signal goes off . So when I drive I have to go with a odb scaner clicking and erasing . What more can be? I have code alternator communication too and change the camshaft position sensor thank you for your time

[@buraksevingul8324]

Fortunately, I have seen this video just after I have experienced same problem. I didn’t read any fault code with elm327. I have changed spark plugs and problem solved. I suspect that the reason of coil failure related to old spark plugs.

[@ionutbloju4189]

What about the 2781 error ? It is related to vanos unit or solenoid ?

[@vanderleycedraz5804]

Qual aplicativo você usa?

[@yongda8203]

👏🏻👍🏻

[@Hardee03]

Hello Sir Bimmerzen, Can you also make a detailed video on how to replace the fuel injectors on this BMW Engine, Many of us will Appreciate that, thank you in advance!

[@spook9375]

Hey man, any guide for exhaust manifold removal or is it dead easy?

[@BimmerZen]

I don't have a guide for that, but it shouldn't be too hard. Nuts and gaskets are supposed to be replaced... You might have to cut the nuts on the exhaust manifold and exhaust pipe flange. They get rusty and seized up.

[@Frank-bc6kn]

thanks a lot for this video, but i have no inpa. where can i this get ?

[@BimmerZen]

Buy inpa dcan inpa cable, make sure you get the one that has a switch for pins so it can work for early and later BMW models. Cables usualy comes with CD with INPA and other sowtware.

[@Moodshroom]

what are you using to read the OBD. I have laptop but don't know how to get these type of apps

[@BimmerZen]

Search youtube for INPA install. Plenty of videos on how to install these programs...

[@ZenTunE-]

What's the reason for the disconnected air pump? Is it the same as mine, where it sounds like a jet engine? :D

[@BimmerZen]

I later discovered that the connector plug was disconnected for some reason:)

[@natcherplays2353]

Coils connectors are practically impossible to plug out for me, also the coils lifter are broken. What can I do?

[@BimmerZen]

Well, you have to pull them out somehow and check why they are so tight...

[@pawel94]

My N42 is also misfiring but I replaced all coils from another car which was running fine and no change. But the interesting thing is that when I unplug Vanos solenoid connector the engine is starting to run like new. Any ideas ?

[@BimmerZen]

You disconnected VANOS solenoid...? Which one, intake or exhaust? Or do you realy mean the Valvetronic position sensor on the top of the valve cover?

[@pawel94]

@@BimmerZen yes, vanos solenoid on the engine front. It doesn’t matter which one I unplug. When I do this while the engine is running it is working rough for about 3 seconds and then I guess it deactivates Vanos and misfiring stops. I thought maybe solenoids are working poorly but I cleaned them out and checked with 12v, they are working fine.. I already changed camshaft sensors and even valvetronic motor but no change

[@BimmerZen]

@@pawel94 What happens if you keep the VANOS solenoids connected but you disconnect just the valvetronic position sensor?

[@pawel94]

Hi, it’s been a while but now I had some time to experiment. 1. Disconnected the Hot-film air mass meter ( the one on the airbox). Engine works nicely, no misfires, but automatic gearbox goes into some kind of emergency mode and has problems with shifting gears smoothly - it kicks with every gear change. 2. Disconnected the eccentric shaft sensor ( the one next to the oil cap). Again, engine works smooth but gearbox is in emergency mode and kicks the gears. 3. Disconnected one of the Vanos solenoids. Engine is working smooth again, no misfiring. No emergency mode on the gearbox - it’s changing gears correctly

[@lelekkozje3049]

NGK coil is ok??

[@BimmerZen]

Go to realoem.com and go to parts catalogue for your specific model, year and month of production. There you will find the specific part number. I dont know about NKG coils, I usually go with Bosch or Delphi.