525iT Misfire/Shudder

Hey guys,

I've got quite a complex situation on my hand so I'll try to describe it the best I can. I currently have a misfire or transmission slip that occurs around 2k from a rolling stop once the vehicle is warmed up.

When cold I get no such hesitation and if I'm moving at a steady speed and give it throttle it's fine.

I first thought it was the TC on it's way out but today I was able to invoke a hesitation enough to trip the SES light and once the light came on it continued to miss until I cycled the ignition or cleared the codes.

I read the codes, cleared them, then went for another drive and was able to trip the light again. Here's the codes that came up:













The OBD codes for cylinder 3 & 5 misfire would come up everytime the SES came on. Now usually I would think if the TC was going I would get an SES for excessive slip or a "trans program" warning but no such thing.

I honestly have no idea where to start when dealing with this issue. I was planning on cleaning the MAF and switching coil packs to see if the problem moves, but the misfire seems to happen at such a specific time, I wonder if it's a complex issue.

Any ideas?

I start by checking the plug wells for oil. Pull the plugs out and look at them. Then swap coils.
Clear all the codes and take it for a ride, see what comes back.

Thanks for the reply, I hope to get a chance to check everything out this weekend, my condo will fine me if they catch me doing anything :/

Originally Posted by Euro_Hobbs

Thanks for the reply, I hope to get a chance to check everything out this weekend, my condo will fine me if they catch me doing anything :/

That's why I hated living in a condo. It's just another government!
1. Family control
2. Condo control
3. Government control
4. Religious control

Anyway, back on topic, this thread 'might' help:
- How to diagnose a BMW E39 engine misfire (1)

Originally Posted by Euro_Hobbs

Thanks for the reply, I hope to get a chance to check everything out this weekend, my condo will fine me if they catch me doing anything :/

Do you get a misfire only at freeway speed when accelerating? I have this & have not found cause.

I'm doing valve cover gaskets, new spark plugs and plug hole oil removal at 90,450 mi. in order to change my original plugs. I had a multiple misfire flashing SES that coded a #4 misfire. I swapped the #1 for the #4 coil and connector and the code shifted to the #1. Then swapped connectors and the code stayed on #1. Replacing that coil.....and all the spark plugs.

Originally Posted by ztom

Do you get a misfire only at freeway speed when accelerating? I have this & have not found cause.

No, at freeway speeds everything is fine...only at lower RPMs do I get the misfire. It seems to be right under 2k

My replacement coil came in yesterday. Installed it on the #1 plug and misfire cured. Mine was running fine at any steady speed. However, when accelerating, like to pass, the engine misfires/ shuddered, flashing Check Engine. Then it started to miss on cold start. Just a coil going bad. Don't over tighten those bolts into the magnesium valve covers.

Swapped the coils around and the misfire followed the pack, I noticed one of the boots was missing part of the rubber around the bottom too. Do you think the packs are still bad or should I try and replace the rubber first?

Now, swap the connectors. If the misfire stays with that coil....it is the coil. However, if the rubber is bad get a new connector. If you then have 2 coded misfiring cylinders on the two you just swapped, then you have a bad coil on one and a bad connector on the other. Simple deduction.