Cold start issue with video

[MisterOadster]

Hi all,

Felicia Sexopants is having a starting issue. A month ago, this was a once a week issue, and it's getting more frequent. This week it's been every morning. This car is daily driven, parked in a garage every night, it hasn't been terribly cold lately.

I've seen some folks in Southern California say their S54 starts a little rough when it's cold outside, but for them that's under 50. I've seen folks from Canada say their starts fine in 30 below. I don't think this is a temperature related issue.

I have heard that these cars don't hold much residual fuel pressure, but it seems to be an issue primarily for those who drive their cars once a week. This car gets driven every day, and as you can see, it was primed before i cranked it over.

It runs fine the rest of the time, it just has a stumble on the first start after resting for the night.

On the M3 forums people will say "that's just the price you pay for a finicky M motor" or "they all hunt at idle" or "mine usually starts on the second attempt, it's normal."

I had an E46 M3 also, and it didn't do this. 8k RPM racy engine or not, it should start smoother than this. My first thought is maybe the fuel filter is getting clogged. It does have 62k miles on it, and it's possible it hasn't been changed, I do have a stack of paperwork for it though. Possible it just needs it again.

Other than that, I don't know if these cars have ignition switch issues or what, so if any of you have experienced this and fixed it, please chime in and discuss. Now for the video evidence.

http://vid283.photobucket.com/albums...ps2bxxmjxb.mp4

[bignosejim]

It maybe started a little slow and it does dip to 400 rpm and back. How old is your battery and does it have a full charge.? Seems to take a little to get it going. That would be the first place I would start to look. Especially if your still on your original battery. It's kinda hard to tell with no codes. Definitely start out with the free and low cost options.

Other than the dip, I think it sounded okay once it got started.

[MisterOadster]

Good point on the battery. If it has a drain somewhere, it may just be leaking electrons overnight, and during the day it's charged more.....

...which might be relevant because every now and then the car loses all electrical while it sits with the key on. Never with the engine running, and it always comes back shortly. Like some interior light circuit has a bad ground somewhere. I hadn't thought to connect the two because the electrical thing only shows up sometimes if i let it sit with the key on for a while like talking to a passenger before we leave, or finishing a phone call when i arrive somewhere and leave the key in it after shutting it off.

I'll check the health of the battery. I'll start with putting a trickle charger on it overnight if i can find one, or add a jump box to it tomorrow morning to see if the boost helps. Not the easiest battery in the world to get to to change it. When I got it it had a loose cable at the terminal I had to take care of.

[Vanne]

Looked ok to me too, id start with my lights turned off btw, less draw.
lol felicia sexopants thats gold!

[ried]

I had this exact issue, which got progressively worse over a couple of weeks, until eventually it stalled on that initial "dip" after a cold start. I had recently been to the dealer for an oil change, and was wondering if they did something to cause this.

Yep, they did.

The tech who changed my oil disconnected the crankcase breather (vent) hose from the top of the black plastic valve cover, but didn't reconnect it. It was laying on top of the valve cover, loose. I pushed the hose back down onto its mount, snapping it into place and the problem was immediately solved.

This is the part, by the way: http://www.ecstuning.com/BMW-E46-M3-S54_3.2L/ES19655/

Hope yours is as easily solved!

[MisterOadster]

Originally Posted by ried

I had this exact issue, which got progressively worse over a couple of weeks, until eventually it stalled on that initial "dip" after a cold start. I had recently been to the dealer for an oil change, and was wondering if they did something to cause this.

Yep, they did.

The tech who changed my oil disconnected the crankcase breather (vent) hose from the top of the black plastic valve cover, but didn't reconnect it. It was laying on top of the valve cover, loose. I pushed the hose back down onto its mount, snapping it into place and the problem was immediately solved.

This is the part, by the way: http://www.ecstuning.com/BMW-E46-M3-S54_3.2L/ES19655/

Hope yours is as easily solved!

A jump box I've used to start a completely dead Dart with a 318 made no difference.

Then I checked the crankcase vent hose, and I did find something amiss. It was on, and seemed secure, but the clip that goes around the fitting is cracked and broken. Enough to not have a perfect seal, certainly possible. It should be fixed anyway since there's no reason to have a cracked vent hose fitting.


Maybe, just maybe that could be it. Thanks for the lead. It's already paid off as something at least damaged.

[StickMon]

If you have access to INPA, you may want to check the Vanos adaptations.
I had this exact issue, with the occasional stall, before I got INPA and found that the "Mechanic" that replaced my camshaft bolts had the exhaust camshaft retarded 14.5°.
That "shudder" that the S54 lets out when you shut it down is the Vanos using pressure stored in the accumulator to hammer the exhaust camshaft to the fully advanced position "for easier starting".
If the camshaft is mechanically retarded so that it's not as advanced as the Vanos thinks it is at start it has to hunt around, resulting in the rev dip.
Since I timed mine correctly, starts on 2-3 revs instead of 5-6, and no more rev dip.
YMMV.

[GP20]

Back in 2006, I used to have this cold start problem on my '04 3.0i. The dealer replaced everything that they could think of and none worked. They contacted the BMW engineers in Germany and was told to try a different gas station and they recommended Chevron. I used to only get Shell gas. After getting my car back I filled up at a Chevron station in a different city that's 30 miles away from the area I lived in; the next day the problem went away.

[UntzUntzUntz]

I've been having the same issue for over a month now. Daily drive it, and only happens on cold start. Not sure if this would have any effect but I've noticed this only happens when I turn on the car and immediately release the clutch. When I keep it pressed it turns on smoothly. Car has just below 50k miles. We must find a cure.

[Daemonblitz]

Just wanted to chime in as well. Mine does the exact same thing. Definitely not battery related. I would say engine temperature related. If it sits overnight and I start it in the morning cold, it will dip, it always only dips once and then steady and smooth from there. The colder it is the heavier it dips. One time only it stalled out completely and had to restart. It didn't bother me too much at first but I would love to get it solved.

EDIT: Here is my cold start

[MisterOadster]

Good, I'm not the only one. We'll fix it. I do have this to say though, that crankcase vent hose listed a couple posts up isn't for my car. This is the one. I'm bummed something for the Z4M is much more expensive than for an E46 M3...but no longer surprised.

http://www.ecstuning.com/ES19659/

[MisterOadster]

Still doing it. The weather here is not cold, but still, when the engine is cold as in overnight or while i'm at work, it still does this. The dealership couldn't think of anything. Bimmerhaus here said one of theirs does it sometimes, but this is now sometimes twice a day. I just want it to start in a smooth way.

[MZHammer]

Originally Posted by Daemonblitz

Just wanted to chime in as well. Mine does the exact same thing. Definitely not battery related. I would say engine temperature related. If it sits overnight and I start it in the morning cold, it will dip, it always only dips once and then steady and smooth from there. The colder it is the heavier it dips. One time only it stalled out completely and had to restart. It didn't bother me too much at first but I would love to get it solved.

EDIT: Here is my cold start

If mine sits for more than a day, I have the exact same start. Funny thing is I went to video it a few mins ago, since I hadn't driven the car since Sunday and it started perfectly, no dip. :

[inTgr8r]

Yes this is common to most of our cars and seems to be gas related, as GP20 mentions
Mine seems to happen occasionally and mostly in cold weather.

[bignosejim]

My car starts a lot easier since I've completed my vanos overhaul. It also runs easier. One easy thing to do from this would be to clean out the vanos valve body. The only consumable part you need would be a sealing plate or a sealing plate o-ring kit ($10). The procedure is detailed here.

Like I said I did all the vanos stuff. My valve body went from not making hardly any noise when holding a magnet to them to nice crisp valve movements after cleaning. This is a pretty easy procedure to do as almost no engine disassembly is required.

[MisterOadster]

Vanos stuff might be worthwhile, I have a coworker who has most of that stuff anyway that he didn't get around to putting on his M3. I think we'll do that this weekend.

[inTgr8r]

Originally Posted by bignosejim

My car starts a lot easier since I've completed my vanos overhaul. It also runs easier. One easy thing to do from this would be to clean out the vanos valve body. The only consumable part you need would be a sealing plate or a sealing plate o-ring kit ($10). The procedure is detailed here.

Like I said I did all the vanos stuff. My valve body went from not making hardly any noise when holding a magnet to them to nice crisp valve movements after cleaning. This is a pretty easy procedure to do as almost no engine disassembly is required.

I'm curious what mileage you were at when you did this.

[bignosejim]

51,000 miles. I did it a couple of weeks ago. That may be something that I add to Inspection II items. It's pretty easy and makes sense to clean out those passages every now and then.

[inTgr8r]

^thanks... that's what I was thinking.

[MisterOadster]

I'm at 62,500 here

[MisterOadster]

I left the car for a week while I was on a trip, and this morning starting it, it stalled twice before catching for good. Something is wrong, and it gets worse the longer I leave it.

[bignosejim]

What have you done so far besides replacing the crankcase vent hose? I would go back to the battery if it isn't new. I'd have it load tested to make sure it is still good. Your original post says that you sometimes lose power when sitting with the key in the ignition...

Other than that, you probably need INPA to have a better look what your engine is up to and to see if there are any other BMW specific codes being stored.