Cyl 6 Misfire after VCG and MILVs install

matteblue3er · 07-14-2020, 08:26 PM

Hey guys so I installed MILVs recently but I accidentally turned the valvetronic motor counter clock wise when removing instead of clockwise. So when I removed the motor, the eccentric shaft sprang back into its resting position.

I now have a cylinder 6 misfire that won't go away. I've tried moving coils, spark plugs, but not injectors. Cylinder 6 injector did have oil in the connector for some reason but I cleaned that up and retentioned all the connector pins for all injectors.

I replaced the ESS with a new sensor but I'm wondering if something got damaged for cylinder 6. The VVT motor was installed with no tension and I relearned the end stop limits via ISTA.

Has anyone made this mistake before and/or know what the possible damage would be from incorrectly removing the VVT motor? The car drives fine and the misfire is only really noticeable at idle

Biginboca · 07-14-2020, 08:36 PM

I had an issue after my MILV’s install. One of the rollers wasn’t centered properly under the MILV. I was only able to diagnose by taking off the Valve Cover again and checking all the rollers. It just needed to be slid properly into place (the roller not the MILV).

IMO your issue has nothing to do with the valvetronic motor. Assuming the misfire started after the MILV install and you have checked everything outside the valve cover (which it sounds like you have) then it’s time to go inside.

matteblue3er · 07-14-2020, 08:55 PM

Quote:

Originally Posted by Biginboca

I had an issue after my MILV’s install. One of the rollers wasn’t centered properly under the MILV. I was only able to diagnose by taking off the Valve Cover again and checking all the rollers. It just needed to be slid properly into place (the roller not the MILV).

IMO your issue has nothing to do with the valvetronic motor. Assuming the misfire started after the MILV install and you have checked everything outside the valve cover (which it sounds like you have) then it’s time to go inside.

Ugh I was afraid of that. I used the spring tool and removed the spring completely so this may very well be the issue. I had checked everything with a mirror but maybe I missed the last cylinder

Biginboca · 07-14-2020, 09:04 PM

Quote:

Originally Posted by matteblue3er

Ugh I was afraid of that. I used the spring tool and removed the spring completely so this may very well be the issue. I had checked everything with a mirror but maybe I missed the last cylinder

At least you know which cylinder to focus on. It will be time consuming but you know what to look for and should be able to get it working!

matteblue3er · 07-17-2020, 07:42 PM

Quote:

Originally Posted by Biginboca

At least you know which cylinder to focus on. It will be time consuming but you know what to look for and should be able to get it working!

Yea I had to reseat 2 rollers. All good now but I had to buy all new gaskets and screws. Didn't want to reuse

hassmaschine · 07-20-2020, 10:51 AM

That sucks, but at least it was a "simple" fix. I suppose this might be the only advantage to my shoestring method, lol.

07-14-2020, 08:26 PM	#1
matteblue3er Captain 238 Rep 947 Posts Drives: Racecar Join Date: Jul 2015 Location: Philly iTrader: (0)	Cyl 6 Misfire after VCG and MILVs install Hey guys so I installed MILVs recently but I accidentally turned the valvetronic motor counter clock wise when removing instead of clockwise. So when I removed the motor, the eccentric shaft sprang back into its resting position. I now have a cylinder 6 misfire that won't go away. I've tried moving coils, spark plugs, but not injectors. Cylinder 6 injector did have oil in the connector for some reason but I cleaned that up and retentioned all the connector pins for all injectors. I replaced the ESS with a new sensor but I'm wondering if something got damaged for cylinder 6. The VVT motor was installed with no tension and I relearned the end stop limits via ISTA. Has anyone made this mistake before and/or know what the possible damage would be from incorrectly removing the VVT motor? The car drives fine and the misfire is only really noticeable at idle Last edited by matteblue3er; 07-14-2020 at 08:36 PM..
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07-14-2020, 08:36 PM	#2
Biginboca Colonel 3762 Rep 2,738 Posts Drives: 2009 E92 328i 6MT Join Date: Jun 2017 Location: Boynton Beach, FL... USA iTrader: (3)	I had an issue after my MILV’s install. One of the rollers wasn’t centered properly under the MILV. I was only able to diagnose by taking off the Valve Cover again and checking all the rollers. It just needed to be slid properly into place (the roller not the MILV). IMO your issue has nothing to do with the valvetronic motor. Assuming the misfire started after the MILV install and you have checked everything outside the valve cover (which it sounds like you have) then it’s time to go inside. __________________ My E92 328csl Build Thread My 328csl Instagram Page
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07-20-2020, 10:51 AM	#6
hassmaschine Major General 3966 Rep 7,215 Posts Drives: "NBO" 330i Join Date: Jun 2014 Location: earth iTrader: (0)	That sucks, but at least it was a "simple" fix. I suppose this might be the only advantage to my shoestring method, lol.
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