Fixing a Misfire in an E60 BMW 5 Series
Tons of troubleshooting has yet to fix a misfire in this member’s E60. Now he needs your help!
When you drive something designed to be truly driven, like an E60 BMW, any sort of gremlin is a real bummer. When you floor it, you expect good things to happen, after all. But after 5Series member skeester wanted to do a little spirited driving recently, that isn’t exactly what happened. Instead of enjoying a quick trip up to speed, a misfire reared its ugly head. So they headed to the forums looking for a solution.
“Has anyone experienced a 29d2 misfire on cylinder 6 after hard acceleration? Initially, I had a whole host of errors related to the VVT solenoids so I replaced both. Now the VVI errors are gone, but it is still running rough. I replaced all 6 injectors and swapped around the plugs and coils, but the misfire stays on the 6th cyl. If I start the car and drive easy, it runs great, no code. As soon as I floor it and accelerate through third gear, the check engine light comes on and it throws the 29d2 code. Any ideas? I would think wiring, but it comes and goes.”
The OP has already done quite a bit of troubleshooting, but NoQuarter offers up a few more suggestions.
“If you are quite certain you have eliminated all possibility that it is not due to a coil/plug/injector, then maybe it is still something specific to that cylinder, such as: DME circuits that drive that coil/plug, coil pack wires, valves, or cylinder. Or it is not just specific to cyl 6 but seems like it is because it is the one that keeps misfiring first. I would get it out on the road and force the misfire numerous times to try and determine if it is indeed always and only a cyl 6 problem.”
The OP has indeed tried to swap coils and plugs around, so seanjordan20 has a few suggestions that essentially sum up anything that could cause a misfire.
“Your problem seems to be the injector/seal, decoupling clip, or O2 sensor. May I ask what brand injector/type you used? Also, if you replaced all injectors did you try to use a good old injector on cyl 6? I am sure all did not go bad.
Make sure the clip on the injector is installed correctly (or installed at all) and check the seal. After that, check your O2 sensors pre-cat bank 2, as it could very well give you a misfire. If your engine is running rough after this, then check for a vacuum leak.”
The OP has already replaced all the injectors with remanufactured BMW parts and new o-rings. Which tends to narrow things down a bit.
“Have you tried swapping injectors 5 and 6? I don’t know if you did the injectors yourself to know how to program them, but I would give that a try. Maybe the 6 is a bad reman. It doesn’t make since for it to start in 2nd and 3rd if something is actually wrong. It would happen all the time. You can’t have a mosfet issue (wrong model for that). Have you done a test on you O2s? I can’t see anything else giving you the issue other than a DME software problem.”
At this point, the OP has ordered new coils and plugs, so we’re awaiting the results of that. But in the meantime, we’re curious to see if you have any insight that might help the OP fix the problem on their E60. If so, head over here and chime in to help a fellow enthusiast!