SOLVED: Another help with codes thread...

[fs34]

My 2008 e90 went into limp mode.

I scanned with an obd 2 scanner and got

P0356 “Ignition Coil F Primary/Secondary Circuit Malfunction”
And
P0357 “Ignition Coil G Primary/Secondary Circuit Malfunction”

A few questions, does “F” mean cylinder 6 and “G” means cylinder 7?

I have a friend coming over to scan with pro tools, but trying to troubleshoot while I wait.

I’ve checked the spark plugs that are easy to get to and they look good. I replaced them and the valve covers approx 5k miles ago.

Any ideas or help is appreciated. I searched and found several threads but nothing conclusive.

[fs34]

So far I have

-checked spark plugs, look good
-moved coils, problem didn’t follow coils
-swapped fuel injectors, codes stayed with cylinders 6&7

Still get the following codes read from protools:

2758 ignition, cylinder 6 activation
2796 no description found
2B57 no description found
2759 ignition, cylinder 7 activation

I am at a loss here. Anyone have any ideas?

[fs34]

At the dealer now.

So far they have repeated all of my tests previously mentioned, no change. They diagnosed broken valve springs. Then they removed the valve cover and the valve train is working perfectly.

Someone on the coding forum pointed to my code 2796 as throttle actuator related. I’m going to ask them to swap them and see. That’s the last part I know to swap here.

They are stumped, I am stumped, any ideas?

[dpaul]

2B57 Motor emergency programm activated
2796 Motor emergency programm activated

These are telling you that something is wrong but nothing about what the problem actually is. They are reflecting the safety measures the DME is taking after detecting the misfires.

Since you found that swapping injectors, plugs and coils have no effect on the cylinders affected and the dealer found broken valve springs (although you don't mention which cylinder), I wouldn't be surprised if there was damaged to cyl 6 and 7 resulting from the spring issue. It wouldn't hurt to have a compression or leak down test to make sure that cylinders 6 and 7 were healthy. If they are, then I'd suspect the DME.

Or did you mean that the dealer suspected broken valve springs but then found they were OK?

[Scrippy]

Has any of the ignition coil wiring been checked/verified? Maybe some wires got damaged at some point?

[fs34]

You won’t believe this...

Previous owner had the throttle actuators replaced at a local shop. Apparently when they installed them they didn’t reinstall the grounding nuts on the engine wire harness towards the back. I couldn’t see that they were missing. This caused voltage spikes which led to the codes.

New grounding bolts installed, cleared codes, car runs fine now.

I’m glad this is over, it’s been a long ordeal that ultimately caused me to have to get a replacement hood which flew up while I was troubleshooting this back in January. The shop that did the work for the previous owner will hear from me. They won’t do anything for me and will deny it but I get to look them in the eye and tell them to eff off.

Man I’ve missed driving this car.

[Drifter2090]

Originally Posted by fs34

You won’t believe this...

Previous owner had the throttle actuators replaced at a local shop. Apparently when they installed them they didn’t reinstall the grounding nuts on the engine wire harness towards the back. I couldn’t see that they were missing. This caused voltage spikes which led to the codes.

New grounding bolts installed, cleared codes, car runs fine now.

I’m glad this is over, it’s been a long ordeal that ultimately caused me to have to get a replacement hood which flew up while I was troubleshooting this back in January. The shop that did the work for the previous owner will hear from me. They won’t do anything for me and will deny it but I get to look them in the eye and tell them to eff off.

Man I’ve missed driving this car.

Glad you got it sorted. Those are the worst kind of issues to diagnose.

[e92.parker]

I know this is an old thread but I wanted to say a couple things.

I am currently chasing down a misfire issue after I just replaced my motor and have gone down the rabbit hole of replacing everything lol. First O2's, spark plugs, coil packs, injectors, secondary air pump and nothing helped with the issue.

Yesterday, I just replaced the whole engine wiring harness thinking that one of the wires got stretched during the swap and after start up I got these codes:

2758 ignition, cylider 6 actuator diag
2759 ignition, cylider 7 actuator diag
and a couple others that were linked to these ^

Car went into limp mode and pretty much reduced all power to the motor. After thinking about it, I forgot to tighten down the top ground on the valve cover and that did the trick to clear the codes.

Hope this helps someone out as this thread definitely helped me out!