eeffinger

Hey everyone,


New to the forum and I promise I did my diligence to find any older posts addressing my issue. I wasn't able to (but please point me in the right direction if I missed something), so I decided to post.


TLDR:

2007 BMW 550i

New battery, TWO new starters, still on crank/no start a few days after changing out battery/starter 1/starter 2

Car will eventually turn over after several tries and letting it sit for a few minutes

Really have no idea what is going on here


My 2007 550i has about 120,000 miles on it and within the past year or so I have had this strange no crank no start issue that would intermittently pop up. It started out happening very irregularly but in the last few months it happens almost every other time I try to start her. It is just a straightforward no crank no start but the electronics, A/C, radio etc. will all turn on. Additionally, there seems to be no rhyme or reason to it. Sometimes it happens when the car has been sitting overnight, sometimes I get in the car in the morning and she starts right up, sometimes it'll start right up and I'll drive to the grocery store just for it to not start trying to get home. I've also never had to get it towed home or to the shop because I can always get it to turn on eventually. I will give it a few shots initially to crank and turn on, and if that doesn't work I will turn the car off and let it sit for a 5-10 minutes and then give it another shot. It has historically always turned on eventually. Additionally, I have experimented with the key in the ignition slot and not just relying on keyless Push-to-Start, but no consistency in turning over with key in or out. I've tried practically standing on the brakes in case there was a vacuum issue not allowing the car to recognize the brakes are engaged, no help there either. It started to happen more frequently and made me late for a work call one morning so I decided to get it looked at.


Although the randomly deciding to turn over on the Xth attempt as I mentioned above was a little weird, I at first figured it was a battery issue. The battery hadn't been replaced in a while and with WFH/Covid stuff going on I rarely drive the car anymore and if I do its a couple miles to the grocery store and back etc. So I took it in around February and the shop told me the battery was at around 30% rem. life so I changed it out. Car starts up perfectly for the first week or so, and then the problem comes back.


So the next step was to change out the starter, which the local shop swore up and down was the cause of my problems even though I was hesitant. $1500 later I have a brand new Bosch starter in there. She starts up perfectly at the shop, drive her around for a few days, perfect strong sounding cranks and the engine starts right up with no issues. On the fourth or fifth day I get in, put my foot on the break, press the Start button, and "click", electronics and A/C on, engine doesn't crank. I go through my usual trouble shooting routine to get it started again, which works, and then drive it directly to the shop and explain the issue. They keep the car another day and when I call up 24 hours later the tech swears to me he has tried to start it 30-40 times and its started perfectly every single time... So, I go back to the shop to get the car since I need it for some family stuff that weekend, and when I go to drive it out of the shop IT DOESN'T START. Same "click", no start. At that point I'm pretty pissed because how did they try to start it 30-40 times and it worked but when I show up it doesn't? But alas, the problem is occurring right in front of them so they are obligated to look into it. They come back saying the starter they got must have been bad.. great. But thankfully the parts and labor are warrantied out so they were able to drop a new starter in for nothing, which I appreciated.


So, now I am on a new battery and my second Bosch starter. Pick her up from the shop, starts up perfectly, drive her around town for a few days running errands etc., including sitting over night a few nights, get in on the fourth for fifth day after the new starter replacement, and what do you know... same issue.


At this point it can't be the starter right? And I doubt it's the battery since it's only a few months old. And since the car will eventually start up after a while it doesn't really make a lot of sense to me that it would be a battery issue (if it doesn't crank on the 1st try, why would the 8th or 9th work, right?).


I am not a car expert and certainly no BMW expert so I wanted to post here to see if anyone has any clue what the issue could be, because I am at a total loss and don't really want to go pay another $150+ diagnosis fee to a different shop just for them to have no idea.


One other piece of information that may be helpful is about a year ago (and I think it may have been around the time my starting issues began but I can't remember exactly). I had a low speed collision on the front passenger side door with a poorly placed concrete pillar in a parking garage (100% me being a dumbass). It was pretty much just cosmetic so I drove around for a few months with the large dent on the door. I eventually got it fixed because I was getting "High Battery Drain" messages upon start up after not driving for a few days and I was thinking maybe the impact threw the door off-track and the car thought the door was constantly ajar or something like that. I have not gotten the "High Battery Drain" messages since fixing the door.


Any input, advice, ideas, or even a solution would be GREATLY appreciated. I really love this car and don't want to get rid of it, but if she isn't going to start up reliably it's just not worth driving around with the possibility of getting stranded. And I really don't want to sink any more money into it chasing a ghost and replacing parts that don't even need replacing.


Thank you for taking the time to read this long winded post!


-Eric

donpb

Next time it won't start, try disconnecting the IBS, the long wire that runs across the battery to the right, and then up, push the connector release clip to unplug it.

seanjordan20

What was fixed on the car from the accident exactly? I would check the spare tire area under the tire to see if the modules have water damage. I would also check the DME under the hood passenger side under the cabin filter to see if you have water damage the. That means unplug your battery and disconnect the connectors to check the modules and connectors for damage. Something has been damaged and hasn't went out all the way. Personally I would keep taking my car back to the ones that swore it was the battery until either they fix it or give me my money back for misdiagnosis. That was $1500 that could of went to what the real issue was. Do not let them get away with waiting your money

donpb

If you disconnect the battery, and connect it back, that's similar to disconnecting the IBS, and that's how it seems like a new battery does the trick. I've been there myself, when I had the exact same issue. I never knew when my car wouldn't start, and AAA couldn't even jump it.

I'd just wait, and it'd finally decide to magically start.

I heard, some roadside services know to disconnect the IBS on BMW's. I did that, and then my car started every single time. I ended up replacing the IBS.

eeffinger

Thanks for the responses. I wasn't able to test this out until just now due to work. Luckily (or unluckily) that gave the car long enough to sit to where it did not crank or start when I tried just now. I went ahead and removed the IBS, which was surprisingly easy to do, and tried to start. No dice. Eventually I was able to get the car to turn so I drove it around the neighborhood for a little while to hopefully charge it up some. Not sure that will really do much, but I am leaving the IBS off over night and will see what happens in the morning. Thanks again

donpb

I forgot to add, if your battery is too low, it still won't start, but if you let it sit for awhile, the battery tends to magically gain back just enough juice to start the car.

A multimeter and battery charger are good tools to have in ones repair arsenal.

eeffinger

I appreciate the extra info. The whole "magically" gets a enough juice is what is really throwing me off on this issue. I am not a mechanic but the totally unpredictable nature of when/why it won't turn or will suddenly decide to turn really confuses me. If she turns on tomorrow morning with the IBS off I am going to drive it into the shop and try to get my $1500 worth since I'm starting to think the starter was never really the problem. Thanks again

Edit- I also saw in my internet investigating that leaving it plugged in to a " Battery Tender" device each night could possibly solve the issue. Might pick one up on Amazon and see if it does anything..

donpb

A battery tender will only mask the root cause, not fix it.

One day, buy yourself a voltmeter, or one that plugs in the cig lighter socket, so you're not totally shooting in the dark.

eeffinger

So what you're saying is similar to @seanjordan20 's comment in that there is something in the car somewhere sucking more juice than it should be and/or not turning off when the car shuts down and that's messing with the IBS and thus not allowing the car to start at random times?

Just want to make sure I'm following the thought process when I try to explain to the shop tomorrow that I do not want a 3rd starter put in..

donpb

Don't go to the shop just yet. Do what you planned first, drive the car for a bit to see if it fails to start with the IBS disconnected.

Did it not start daily or? If it was daily, and then you go at least 5 days without it happening, then you're on the right track.