Misfires/rough driving after VANOS work!

[cnano8]

Hey guys so I've just finished up installing a new exhaust hub since my old one was cracked. Both tangs were broken off in the oil pump disc but thankfully stayed in there which saved my engine! Dr Vanos re-drilled my disc for me with smaller holes and I put in a new oem exhaust hub assembly including the timing chain gear. While I had the vanos removed I rebuilt it using the Beisan kit and following their detailed instructions and that seemed to go just fine.

Before I go any further, *full disclosure* while removing the vanos solenoid I dropped it like a jackass.. It landed right on the connecter part and a piece of it broke off. The harness connector still goes on and stays there with a zip tie. I know these things are prone to having the solder joints crack under normal conditions, never mind giving it a 3' drop to a concrete floor so it may be f*cked but I dk. I did clean the solenoid assembly using magnets and brake cleaner as directed in the Beisan instructions.

So I finish the install, the splined teeth are in their correct slots (first available tooth etc), checked cam timing with the alignment bridge, rotated engine by hand and checked again. I was fairly confident this job was done so I buttoned things up and nervously fired up the car. It started fine, idled fine and revved fine (idle-2.5k rpm) so I burped the cooling system and stopped for the night. The next morning I put the car on the ground and again it started fine, idled fine and warmed up as normal. I took it for a test drive just slowly cruising around my neighborhood in 2nd, 3rd and 4th gears letting the car get to temperature. The car was running like new then about 10 minutes or so into cruising the car started stumbling and misfiring badly. In my head I'm thinking wtf is this about the car was just fine.. then it proceeded to get a bit worse with the stumbling and to a point where the car was barely drivable and threw the SES light (codes below). The exhaust note sounded like a Subaru. I babied it home and pulled the valve cover thinking my timing was off or something because I was relatively sure the ignition coils weren't bad but now I'm not so sure because I believe they're Bremi coils. NGK spark plugs only have 10k on them.

My thinking is I have 3 possible problems:

• Messed up the hub/vanos install and timing is not correct (this does not explain why the car drove fine for the first 10 minutes)
• Coil packs went bad during the test drive (would explain why the car ran fine for 10 minutes then had issues)
• Vanos solenoid is bad from me dropping it on the floor (im not sure if this will cause immediate issues during cold start or not)

NOTES/NEW PARTS (all oem bmw parts besides beisan)
'06 M3 ZCP with 51000 miles

-Exhaust hub assembly
-Beisan vanos rebuild
-timing chain guide
-timing chain tensioner
-coolant expansion tank
-all coolant hoses
-waterpump
-thermostat

SES Codes
P0420 (had this thrown a couple times before from my exhaust)
P0430 (had this thrown a couple times before from my exhaust)
P0300
P0302
P0305


What do you guys think? Any help would be appreciated. Thanks

https://drive.google.com/file/d/0B0i...ew?usp=sharing (cam pics)
https://drive.google.com/file/d/0B0i...ew?usp=sharing (cam pics)

[dworthy]

Welcome to the Forum!

Yes I too am having my fun with VANOS issues from Dr. VANOS, as in they didn't drill the oil pump disk properly, but I digress.....

So the first two codes is probably a bad oxygen sensor.
The next 3 are misfire codes, I would pull cylinder 2 and 5 to ensure you have the sparkplug installed properly, and the coil is also seated all the way.

Do you have anything besides a hand scanner? How about INPA so you can watch the live data from the cams? Or even the rough running?

A lot of BMW tech's do not like "P" codes as they are government mandated codes and can be rather vague when it comes to diagnosing a car. I am sure there will be more codes in the shadow memory, and there is where INPA comes in to pull those out.

[cnano8]

Thanks for the welcome and reply. Im sorry to hear your oil pump disk is messed up. I didn't have any issues with mine, fitment wise. It was deff more tighter than the stock holes when I turned it back and for with the hub.

On the P04 codes I think they have been coming on and off because the car has a full supersprint exhaust with headers.

I figured I would check the timing end of things before I put the valve cover back on and check the coil packs. Im thinking if I did not have the timing set correctly then shouldn't of it ran like shit from the first start? I just find it odd that it cold started and warmed up fine twice and also drove fine for 10 minutes before have any issues at all. Which had me start thinking about looking at the coil packs.

I don't have INPA just a little scanner. Ill check it out because I have some software for my Evo that is really nice to use for things like this.

[dworthy]

Yes, having catless headers will cause those two codes. What I would recommend is getting a O2 defouler install on them to keep the codes away especially for inspection.

If the timing was out, you would get a cam code, something like P0011/0012 for cam timing. I think there is something else going on, and yes I have seen coils just fail too.

In order to use INPA, you just need a cable and the software. On this Google is your friend

[cnano8]

Thanks for the reply and help, it is much appreciated. My friend also suggested the same thing you mentioned that it should be throwing other codes if the timing was incorrect. As a easy check ill be putting the valve cover back on today and checking the coils packs to rule them out. Ill report back what I find. Thanks

[dworthy]

What you can do is move #5 to #6 and see if the misfire follows. You can do the same with #2, move it to #1. This can rule out the coils if the misfire doesn't move and show up as P0301 and P0306.

[cnano8]

So I moved the 2nd coil pack into the 3rd cylinder and the 5th pack into the 6th cylinder expecting to see P0303 and P0306 with a very bad idle. I start the car and to my surprise it starts and idles just perfect!? I let it sit and idle for about 5-10 minutes and give it a little gas to move the rpms around a bit and it was fine. So I decided to take it for a drive and 10 minutes in everything is running perfect so I start driving it a little more aggressively to get the vanos to operate a bit more. I drove the car for about 45 minutes and did a couple 3/4 throttle runs to 6k and it ran beautifully without a hiccup. I swore I was going crazy but I was happy that the car seemed fine but still nervous that I didn't fix the problem. When I got it home I scanned it just to see if anything would come up and it did not have any codes. Im now thinking that I originally did not have the coil packs pushed down all the way which caused the misfire. Ill be driving the car more tomorrow just to confirm things are good. If symptoms do come back ill post it in here. Thanks

[dworthy]

Good to hear that all is well!

What I would do is attempt to seal that VANOS solenoid connector, for any moisture gets in there, will cause problems. These guys sell rebuilt/used ones for pretty cheap: http://www.beisansystems.com/products.html