[MyPocketsHurt]

Hi guys looking to finally figure out this issue I’m having with my 2011 335i n55

Car would originally start up but when engine is shut off and try to start back up. Weak crank by the starter and no start then eventually just clicking. However, letting the car sit for hours, the car would start but still with weak crank. Jumping it the first time it originally did not start did not work either.

Replaced starter.

Car still did not start just click. Tried jumping it again and it started each time. 2 days later tried to start and didn’t. Tried to jump it, no start just click.

Checked battery through multimeter and it was drained to probably around 8.5v when measured.

I’ve checked both ground straps and they are in good condition and all cables from the battery are in good condition and not loose.

I must add that my waterpump has been activating when unlocking/opening the doors and when the car is turned off which is causing my current battery to get drained. My guess is that it’s drained my battery and has killed the cell causing my no start.

I do have a new battery that is not registered to the car but do not want to swap it and have it drain and die either.

So my question is. Is this a bad waterpump or something else causing the pump to run? And is this likely the reason I’m getting no start from battery being fried even when jumping from a car?

[gbalthrop]

Check your Transfer Points at forward base of Battery. If Voltage at Jumpstart Terminals under hood is LESS than voltage
at Battery Posts in Boot, the OutBoard Transfer Point is likely failing/ rusted.
George

[MyPocketsHurt]

Originally Posted by gbalthrop

Check your Transfer Points at forward base of Battery. If Voltage at Jumpstart Terminals under hood is LESS than voltage
at Battery Posts in Boot, the OutBoard Transfer Point is likely failing/ rusted.
George

Hi thanks for your feedback. I forgot to mention in my post but I’m getting the same voltage at the posts under the hood and at the battery. I did throw a charger on the battery and it’ll charge up but start to die with nothing affecting it. Believe it’s damaged.

[NZE90]

Charge up your new battery so it is fully charged, then install it in your car. If the problem is still there then just disconnect the negative terminal so it won't drain. The battery you have in there now is bad. Trying to troubleshoot a vehicle with a bad battery is impossible.

And while you have battery out, check the battery cable pass through points as suggested above. They are known to corrode and cause starting problems.

[MyPocketsHurt]

Originally Posted by NZE90

Charge up your new battery so it is fully charged, then install it in your car. If the problem is still there then just disconnect the negative terminal so it won't drain. The battery you have in there now is bad. Trying to troubleshoot a vehicle with a bad battery is impossible.

And while you have battery out, check the battery cable pass through points as suggested above. They are known to corrode and cause starting problems.

Sounds good I will give this a shot tomorrow. In regards to the new battery it’s good with just the negative off don’t need to disconnect the positive right? Thanks

[MyPocketsHurt]

Originally Posted by MyPocketsHurt

Sounds good I will give this a shot tomorrow. In regards to the new battery it’s good with just the negative off don’t need to disconnect the positive right? Thanks

Just to add on to your post. Someone told me doing this could blow a fuse since the water pump is probably gone bad. What are your thoughts? Still safe to try and start it with new battery and give it a shot?

[NZE90]

Yes it is completely fine to just disconnect the negative. The statement about possibly blowing fuses is nonsense. Kind of like saying "Don't drive your car because you might have a crash"

[MyPocketsHurt]

Originally Posted by NZE90

Yes it is completely fine to just disconnect the negative. The statement about possibly blowing fuses is nonsense. Kind of like saying "Don't drive your car because you might have a crash"

Thanks. I’ll give it a shot tomorrow with the new battery in. You think that water pump just needs to be replaced then as well?

[NZE90]

Maybe, but it should be diagnosed properly first before replacing any parts. Otherwise you risk spending money needlessly.

[MyPocketsHurt]

Originally Posted by NZE90

Maybe, but it should be diagnosed properly first before replacing any parts. Otherwise you risk spending money needlessly.

That’s what I figured. Anyways I can diagnose at home to see if it’s going bad? I don’t currently have a code reader but one coming this week other than that any ways?

[NZE90]

Personally i wouldn't bother until you have your reader. Put the new battery in the car first and see how you go with starting it.

[MyPocketsHurt]

Originally Posted by NZE90

Personally i wouldn't bother until you have your reader. Put the new battery in the car first and see how you go with starting it.

So update. Put in the new battery and still no start. Had a shit ton of codes from old battery which I will include. Then cleared all. Put new battery and just getting the IBS Code now.

[NZE90]

That shadow code for the valvetronic could be an issue. Can you run the valvetronic initialization with your software?
What is your cranking speed like? Can you post a video of it when cranking?

[MyPocketsHurt]

Originally Posted by NZE90

That shadow code for the valvetronic could be an issue. Can you run the valvetronic initialization with your software?
What is your cranking speed like? Can you post a video of it when cranking?

I can’t even get it to start so can’t even get it to crank. My Positive cable wire is shredded which I believe is causing the no start. I’ll replace it and check codes again if it starts.

[NZE90]

I see. Did you check the battery cable pass through connections when the battery was out?

[MyPocketsHurt]

Originally Posted by NZE90

I see. Did you check the battery cable pass through connections when the battery was out?

Yes everything else was all good seems like just this positive cable going to the starter up front is toast