[5hpstickers]

I just took the charger off the battery and then used a multimeter to check voltage numbers at the battery posts under the hood and also checked at battery terminals.

Both were very close at around 12.3-12.4 V still not starting.

Disconnected blue IBS wire and attempted to start, still nothing.

Next step is to leave battery off charger with IBS off to see if voltage drops over the next few hours. That should let me know battery is no good correct?

I also looked at "eye" on battery and it does look black when looking at it. Tried to take pic of it with flash and you can see some green but I'm assuming that may be because of the flash?

[5hpstickers]

Battery has not lost any voltage and is reading 12.5V when out of the car.

Going to go get it tested at pepboys and see what happens. If anything I will get a new one and register using BMWLogger and give an update.

[5hpstickers]

Got the battery checked at pep boys. Guy said it only had 9.6 V when he hooked it up. He charged it up and tested and said it's good.

So I took it straight home to give it a shot, still nothing.

Then we took a booster cable from the ground for jumping the car under the hood, to a point on the block and it actually was cranking so I believe it might be the engine ground strap. Can anyone tell me where it is or give me a pic pointing it out?

Thanks again everyone

[5hpstickers]

bump for engine ground strap location please

[5hpstickers]

Found the engine earth strap by the driver's side motor mount and the cable is broken so I found my issue.

Now I just have to find the part number to order it.

Will take a pic of the cable once I get it out.

[///Mposter]

That's great news that you found it. I'm interested in where its located and maybe how you think it broke.

[JamesM3M5]

Glad you found the problem! The engine ground strap is there to not only ground the starter for cranking but all of the other items that are bolted to the engine - some sensors, the water pump, and the alternator.

I've seen the muffler ground straps on E9x M3s break - they get saltwater in them from the winter and it turns the soft, fine-stranded braided copper hard as a rock. With engine vibrations, you may have a hardened cable that snapped off - typically right at one of the crimp ends.

Sorry I didn't see your request for ground strap location. I couldn't remember where it was anyway, though.

[5hpstickers]

Originally Posted by JamesM3M5

Glad you found the problem! The engine ground strap is there to not only ground the starter for cranking but all of the other items that are bolted to the engine - some sensors, the water pump, and the alternator.

I've seen the muffler ground straps on E9x M3s break - they get saltwater in them from the winter and it turns the soft, fine-stranded braided copper hard as a rock. With engine vibrations, you may have a hardened cable that snapped off - typically right at one of the crimp ends.

Sorry I didn't see your request for ground strap location. I couldn't remember where it was anyway, though.

It's ok no problem. I definitely think you are correct in why it broke because it did break right at one of the ends.

The strap is located on the driver's side motor mount and can easily be accessed by removing driver's side front wheel to see the strap and then some plastics to actually get to the bolts.

I just need to find a part number or may possibly use a battery ground type cable that has rubber to protect the cable from elements.

[N8N]

If you want your car to be show correct get the factory strap otherwise anything of sufficient gauge and with the right ends will work electrically...

[5hpstickers]

Originally Posted by N8N

If you want your car to be show correct get the factory strap otherwise anything of sufficient gauge and with the right ends will work electrically...

I guess I will have to call the dealer as I cannot find the part on getbmwparts.com

[SteveAZ]

If so...its $28.18 on getbmwparts

[5hpstickers]

Originally Posted by SteveAZ

If so...its $28.18 on getbmwparts

You the man!!!!

[hurleypatrick]

Originally Posted by JamesM3M5

Glad you found the problem! The engine ground strap is there to not only ground the starter for cranking but all of the other items that are bolted to the engine - some sensors, the water pump, and the alternator.

I've seen the muffler ground straps on E9x M3s break - they get saltwater in them from the winter and it turns the soft, fine-stranded braided copper hard as a rock. With engine vibrations, you may have a hardened cable that snapped off - typically right at one of the crimp ends.

Sorry I didn't see your request for ground strap location. I couldn't remember where it was anyway, though.

If the ground strap is broken will the fuel pump still work? I am getting a whirring and I think it's the fuel pump. Also I'm obviously just getting a click when pressing the ignition.

Hook up a temporary ground strap and see if you get a different result.

[Cm452]

Zombified, but, my ground strap on the driver's side engine mount bracket has turned to dust, leaving no indication of where on the chassis the damn thing connects. There is a huge ground strap from the bellhousing to the chassis, but other than that, I cannot see where it would go...anywhere. There is just the lug sticking out from the bracket.
OP, do you remember where, exactly, the chassis-side of that strap ended up going?

[ayzzz]

The same problem just occurred to me. I first thought it was only the battery and had that replaced; however, it turned out to be my alternator. Along with my alternator going out, my water pump went with it. I doubt it is anything connected. Just keep your eye out for any other things that may seem off with the car.

[jonnybthegoalie]

I had the same problem, replaced the battery and alternator and still no start! Finally, after a lot of digging found this thread and saw my ground strap was all corroded. Replaced and now runs great!