[madmatt9471]

Here is a little quick history. This is my daughters 2008 BMW 335i E90 N54 Automatic with just a little over a 100,00 miles, thing runs fantastic.

However it had the infamous oil leak on the Valve Cover and also on the front of the engine ledge where it would seep oil and run down and make a mess everywhere. So I decided to fund the repairs, since I just had spine fusion and cannot do any of the work myself, labor and parts. From the new Head Gasket all the way to the Valve Cover (all Bolts and gaskets that were needed).

Already have: Bentley Manual for this specific 2008 BMW 335i

The mechanic did everything here at my home, bringing all his tools etc. to do the job (SAE certified mechanic and good friend).

Everything went smooth, when it went back together, had all the N54 timing tools, crank pin etc.

Battery is unplugged through the whole process so no shorts will happen, also put on a tender.

So let's fast forward to the start up - Started it up and it ran rough, pulled an initial code with a general code reader and got a:

P0015 (2A87) 'B' Camshaft Position Timing Over-Retarded (Bank 1)

Okay no problem, looked up the code and found that many times it can be caused by the Vanos Solenoid - So the mechanic said I am going to check the timing again, he pulls everything apart and the timing is spot on. So I decided to order two new Vanos Solenoids, locally they have them at Oreilly Auto Parts - Great. Put them in and same issue.

RUNS THE EXACT SAME. Like its is missing but really consistent. I decide it is time to order the Foxwell NT510 and mechanic is going to come back next week. to run some checks and see if there is a sensor that is damaged or something.

Following week: Start the car plug in NT510 and get the codes -
(1) 30A3 (P2310) Ignition Coil Primary 'D' Circuit High (Coil 4)
(2) 30A4 (P2313) Ignition Coil Primary 'E' Circuit High (Coil 5)
(3) 30A5 (P2316) Ignition Coil Primary 'F' Circuit High (Coil 6)

Translation:Faulty ignition coil, Short or open in the wiring, Corroded connector on the ignition coil, or Failed PCM (rare)

Get this the #5 coil gets really HOT out the back 3 coils, so he switches the coils around and it cools down in position #1, #1 coil is now in #5 spot and it gets HOT when the car starts. Did this with another coil and same results.

So 1/2 the engine is not firing. Bank 2 coil system. Something is not telling the DME to ignite the coils (send the signal ground to it) and also it will not fire off the injectors.

Tests performed and Inspections performed:

(1) Switched front injectors to the rear to see if it is the injectors - no change
(2) Switched around coils no change (with the exception #5 gets HOT like when you pull it out it is hard to handle)
(3) Inspected for any frayed or pinched wires, harness or otherwise, going to the DME - none
(4) Inspect bank #2 wire harness for the *** O2 sensor, for any damage - none
(5) Double and triple checked all electrical connections to be tight and solid - good
(6) Checked all grounds to Injectors and Coils - good and intact
(7) Checked to make sure that each coil is wire is in its proper place and goes where it is supposed to be from the DME - good all in proper order from DME
(8) Make sure each coil has its 12 volt ignition source when ignition is on - good
(9) #5 position coil wires and connection fully inspected to ensure there is no shorting out
(10) Unplugged coils to see if there would be any change - none, ran the same.
(11) Two new Vanos Solenoids (due to a code we had at one point P0015 or 2A87 which Vanos solenoids usually trigger)

QUESTIONS:

(1) What would stop the DME to send the signal to the #4-6 coils? Remember the #1-3 coils are firing
(2) What sensor(s) tells the DME it's okay to fire the coils? Bank 1 #1-3 and Bank 2 #4-6

My thought is that there has to be something TELLING or NOT telling the DME its OKAY to fire the rear coils - now as to why the #5 (middle coil) is getting HOT, well that's a mystery and maybe part of the problem.

The mechanic is going to go to his BMW specialist next to his shop and see if he can get schematics and diagrams as well as trouble shooting diagnostic procedures for these particular codes, since the Bently Manual does NOT have the breakdown of them.

So any thoughts or experience with the same issues or input would be greatly appreciated and I can pass it along.

Thanks,Matt
661-406-7516
I live in Palmdale, CA 93552. If anyone can help out or know of someone who might be able and willing to help, that would be great.

[madmatt9471]

Update: Either way if this helps someone this is what it is all about, I have gotten a little direction from some other BMW Forums - and I believe that we are onto something! See below.

I did not or have not gotten a 30BA or 30BB, as of yet - but that does not mean we won't check again, just to make sure.

This certainly sounds like it is going to be it, Mosfet, or at least in the DME, because I was able to go out to the BMW and do a little test on the #5 Coil connector -

The connector itself is fine and not melted or anything like that -

#5 coil connector wires: White/Blue goes to DME and is ground signal from it;Orange goes to the interference suppression capacitor; Brown goes to the chassis ground on the manifold post

(1) I took a continuity tester and tested the Brown from the connector to the post and it beeped fine wire is good, doing what it should

(2) I put one end of the continuity tester on the Brown lead in the connector and put it on the Orange in the connector and it beeped as it should

(3) I put one end of the continuity tester on the brown (Ground) and the White/Blue (Grounding signal for the coil from DME) going into DME and it "BEEPED" - which it should NOT, it should be open and not closed or shorted out. Inside the DME the #5 coil is grounding out. The MOSFET for #5?

(4) I ran the same test on all the remaining 5 coils and the test #1 and #2 same result as above, but NOT #3 , the tester did not BEEP, because the coil wire going into the DME is open like it should and not closing until the DME tells it to when it fires or grounds the coil to fire the plug.

At this point and only being a little over three weeks out of spinal fusion, with rods and screws in my back, I was in pain and had to stop.

I will at this point either have to send the DME out for repairs or order a new DME and have the "STEALERSHIP" code the New DME to the car, oh and yeah have the car towed to the Stealership. Oh my aching back.

Thank you to everyone who helped up to this point - I am one who always keeps things updated on my threads, either it be a BMW or Corvette thread. I will post results and direction that I went.

Be aware that I will not be able to do or have anything done till this weekend when I can get help or when the mechanic is coming over.

Thanks,Matt
661-406-7516

[CantComplain]

Man, tough break. I feel your pain. I've been in this situation before, though of course not exactly. But you're doing the right thing for the right reason and BAM! you get screwed by something new.

I'm not the most experienced guy around these cars so I can't offer up any technical advice here. But based on what changed and what occurred, I can't help but think the MOSFET is a red herring. Not that it's not bad even, just that you didn't mess with anything even remotely related and you had the electrical system disconnected. I'm not sure how that could have happened except in an EXTREMELY coincidental occurrence. But you have what appears to be a bad ignition situation in cylinder #5 regardless. For someone unfamiliar with the specifics of the ignition system at this level it sounds like you've done some solid diagnostics.

But. Do you think there's any chance that they're not related? Any issues for a car that was running fine before a change that now runs differently is most likely a result of the change. I've seen posts of people getting vacuum hoses and the like not hooked up correctly, certified mechanics even (especially!) and they cause odd issues. If your friend doesn't specialize in this car it could be a simple re-assembly mistake and maybe you ran across the older error because you were looking so hard for the cause of the new one.

Or I could be talking out my ass. Either way you have my sympathy and I wish you the best of luck. Please post an update to help others in the future.

Originally Posted by madmatt9471

Update: Either way if this helps someone this is what it is all about, I have gotten a little direction from some other BMW Forums - and I believe that we are onto something! See below.

I did not or have not gotten a 30BA or 30BB, as of yet - but that does not mean we won't check again, just to make sure.

This certainly sounds like it is going to be it, Mosfet, or at least in the DME, because I was able to go out to the BMW and do a little test on the #5 Coil connector -

The connector itself is fine and not melted or anything like that -

#5 coil connector wires: White/Blue goes to DME and is ground signal from it;Orange goes to the interference suppression capacitor; Brown goes to the chassis ground on the manifold post

(1) I took a continuity tester and tested the Brown from the connector to the post and it beeped fine wire is good, doing what it should

(2) I put one end of the continuity tester on the Brown lead in the connector and put it on the Orange in the connector and it beeped as it should

(3) I put one end of the continuity tester on the brown (Ground) and the White/Blue (Grounding signal for the coil from DME) going into DME and it "BEEPED" - which it should NOT, it should be open and not closed or shorted out. Inside the DME the #5 coil is grounding out. The MOSFET for #5?

(4) I ran the same test on all the remaining 5 coils and the test #1 and #2 same result as above, but NOT #3 , the tester did not BEEP, because the coil wire going into the DME is open like it should and not closing until the DME tells it to when it fires or grounds the coil to fire the plug.

At this point and only being a little over three weeks out of spinal fusion, with rods and screws in my back, I was in pain and had to stop.

I will at this point either have to send the DME out for repairs or order a new DME and have the "STEALERSHIP" code the New DME to the car, oh and yeah have the car towed to the Stealership. Oh my aching back.

Thank you to everyone who helped up to this point - I am one who always keeps things updated on my threads, either it be a BMW or Corvette thread. I will post results and direction that I went.

Be aware that I will not be able to do or have anything done till this weekend when I can get help or when the mechanic is coming over.

Thanks,Matt
661-406-7516

[CantComplain]

And regarding the troubleshooting the coil short on #5, it sounds like all of the testing you did is at the coil connector itself. Have you run the MOSFET test on the DME? It's stupid simple once the DME is out, and that's not tough either.

[madmatt9471]

Originally Posted by CantComplain

Man, tough break. I feel your pain. I've been in this situation before, though of course not exactly. But you're doing the right thing for the right reason and BAM! you get screwed by something new.

I'm not the most experienced guy around these cars so I can't offer up any technical advice here. But based on what changed and what occurred, I can't help but think the MOSFET is a red herring. Not that it's not bad even, just that you didn't mess with anything even remotely related and you had the electrical system disconnected. I'm not sure how that could have happened except in an EXTREMELY coincidental occurrence. But you have what appears to be a bad ignition situation in cylinder #5 regardless. For someone unfamiliar with the specifics of the ignition system at this level it sounds like you've done some solid diagnostics.

But. Do you think there's any chance that they're not related? Any issues for a car that was running fine before a change that now runs differently is most likely a result of the change. I've seen posts of people getting vacuum hoses and the like not hooked up correctly, certified mechanics even (especially!) and they cause odd issues. If your friend doesn't specialize in this car it could be a simple re-assembly mistake and maybe you ran across the older error because you were looking so hard for the cause of the new one.

Or I could be talking out my ass. Either way you have my sympathy and I wish you the best of luck. Please post an update to help others in the future.

Cantcomplain,

Thank you for the response buddy.

Went over everything and he is coming up again this Sunday to comb over every hose and electrical connector again - he was a BMW and Porsche mechanic before becoming a GM mechanic too.

I am hoping for the best! I am going to respond to your post with the Mosfets next!

Thanks,Matt

[madmatt9471]

Originally Posted by CantComplain

And regarding the troubleshooting the coil short on #5, it sounds like all of the testing you did is at the coil connector itself. Have you run the MOSFET test on the DME? It's stupid simple once the DME is out, and that's not tough either.

Going to look into this before anything goes further - it can just be a rare occurrence that happened - who knows at this point - heck it could of been one of those things that was just ready to go.

We will get it sorted out - just a little more investigating to do

Watched the video! Thank you!

Thanks,Matt

[madmatt9471]

I made an inquiring phone call about MOSFETS to SIA (Company whom repairs Mosfets and the DME) http://siaelec.com/product/bmw-3-ser...repair-return/

Speaking with a Tech I asked:

Me: Does "EACH COIL" also have a MOSFET?

Tech: Yes, each coil does indeed have a Mosfet.

I explained the whole scenario to him (almost like the information in the post above) to give him the details, ESPECIALLY the grounding out of the Whit/Blue wire on the connector.

He reassured me that this is something that can be repaired -

So now I am going to have the DME pulled and before anything, gonna open it and test the Mosfets and find that #5 Coil bastard that is causing all this trouble.

I will probably have to have someone else do the Mosfet replacement and I am considering having "ALL" of them replaced so in the near future we don't have to go through this again.

Thanks,Matt

[madmatt9471]

Got the DME/ECU pulled today and also the removed the cover and it turns out the the #5 Mosfet for the coil is "BAD" - see diagram below for the location of the #5 Coil Mosfet -

As far as the rest of the coil Mosfet locations I don't know - it is packed and ready to be shipped for repair -

[CantComplain]

Originally Posted by madmatt9471

Got the DME/ECU pulled today and also the removed the cover and it turns out the the #5 Mosfet for the coil is "BAD" - see diagram below for the location of the #5 Coil Mosfet -

As far as the rest of the coil Mosfet locations I don't know - it is packed and ready to be shipped for repair -

so when I had my DME out to test the same thing (I had what I thought was a fuel delivery issue--it wasn't) the injector mosfets all behaved the same way but the other ones did not test out with the same characteristics. So if that's what you're basing your thinking on, it may be flawed.

The MOSFETS that are known to fail control the injectors; I don't know that I've heard about MOSFETS controlling coils. I just want to make sure you don't go too far down the wrong path in troubleshooting this.

Sorry I can't provide any more useful data.

[madmatt9471]

Originally Posted by CantComplain

so when I had my DME out to test the same thing (I had what I thought was a fuel delivery issue--it wasn't) the injector mosfets all behaved the same way but the other ones did not test out with the same characteristics. So if that's what you're basing your thinking on, it may be flawed.

The MOSFETS that are known to fail control the injectors; I don't know that I've heard about MOSFETS controlling coils. I just want to make sure you don't go too far down the wrong path in troubleshooting this.

Sorry I can't provide any more useful data.

I hear you on what you are explaining and it is no wild chase by any means -

It has been confirmed that the DME (MS80) does indeed have Coil MOSFETS too -

The repair has been made and I am expecting it back soon - I thought it prudent and the course of wisdom to send it out and have the entire DME tested and any and all repairs done as needed -

Thanks,Matt

[madmatt9471]

The DME (MSD80) is in the BMW now, as of today, and is up and running exceptionally well and no oil leaks or anything else - all codes are gone and all is in perfect running condition -

I did also replace "All" coils for my daughters car too, with BOSCH coils, since those were stock and had over a 100,000 miles on them -

And replaced the plugs!

Thanks to everyone who helped -

It's $219 total no matter what they have to fix, fully tested and inspected and that is shipped back to you as well -

To me it was well worth the inspection and thorough component inspection of the whole unit and circuit board for peace of mind - Small price to pay for what we can pay on these cars (well for some of us on our daughters car)

Thanks,Matt

[335e92tx]

good deal

[madmatt9471]

Originally Posted by 335e92tx

good deal

Thank you - I'm glad too, really glad!

It's $219 total no matter what they have to fix, fully tested and inspected and that is shipped back to you as well -

To me it was well worth the inspection and thorough component inspection of the whole unit and circuit board for peace of mind - Small price to pay for what we can pay on these cars (well for some of us on our daughters car )

Thanks,Matt

[langsbr]

Good info - sorry you had the trouble, but thanks for sharing it@

[madmatt9471]

Originally Posted by langsbr

Good info - sorry you had the trouble, but thanks for sharing it@

Right on - that's what the Forums are for, and we save each other a lot of headache and money too!

And at the very least we are informed so if we should have to go to the dealership we go with our eyes open!

Thanks,Matt