128 won't start?

[Kev312]

The weather has been nice so I've been driving my other car. 128 has sat for maybe 5 days. Went to drive it to work this morning, put the key in the slot, hit the start button and it hesitated "slightly", then progressively hesitated until it barely wanted to turn with each press.

I've let the car sit for a week before with no issue. So I checked the battery with a multimeter and it's sitting at about 12.47 while not running so I know it has plenty of power. Thoughts? I've heard of cars needing to be driven every so often to keep antitheft in a normal state, so I'm not sure if this is the case and how to resolve it.

Thanks in advance.

[NorthernDancer]

loose or dirty connections. Check your battery cables VERY carefully, both in engine compartment and in trunk.

[Manual Transmission]

5 days is nothing. I second the battery connection recommendation. Likely a tiny bit of corrosion or loose terminals is causing the issue.

[Kev312]

Checked all the terminals and cables and nothing seems to be loose. It started perfectly fine the last time it drove about a week ago. Could it have anything to do with anti-theft?

[02Pilot]

I doubt this is an anti-theft system issue. Put a booster box on it or jump it - if it starts normally you'll know it's battery issue.

[Kev312]

Wouldn't jump with a boost from my other car yesterday after work. In fact, it didn't seem like it had any effect on the car attempting to turn over. Small hesitation but that was it.

[Bimmer-Bob]

Originally Posted by Kev312

Wouldn't jump with a boost from my other car yesterday after work. In fact, it didn't seem like it had any effect on the car attempting to turn over. Small hesitation but that was it.

Can you pull fault codes?

[Kev312]

Originally Posted by Bimmer-Bob

Can you pull fault codes?

Yeah that's my next step today, hopefully there is something stored that can help pin point what's going on.

[02Pilot]

Originally Posted by Kev312

Wouldn't jump with a boost from my other car yesterday after work. In fact, it didn't seem like it had any effect on the car attempting to turn over. Small hesitation but that was it.

Did you attach the cables at the terminals in the engine bay or at the battery? Have you checked continuity of the battery negative terminal to ground?

Concur that you need to get the codes before proceeding further.

[Kev312]

Originally Posted by 02Pilot

Did you attach the cables at the terminals in the engine bay or at the battery? Have you checked continuity of the battery negative terminal to ground?

Concur that you need to get the codes before proceeding further.

To the terminals in my engine bay since I know the connections there are fine (had to use to jump start my other car in the past). I'll try the battery today for shits and gigs.

I'll run it for codes today, but also going to check the starter and see if it's getting power.

[MotoWPK]

12.47V static is a likley indication of a dead battery or largely discharge battery. A healthy, charge battery should be closer to 13V. Also, it's quite possible that a dead battery will prevent jumping with another battery (e.g. an internal short will suck up almost all the amps available from the other battery).

Before replacing the battery, though, always check the terminal connections, and not just to feel if they are loose. Disconnect and clean them.

[Kev312]

Might be a dumb question but, can I grab a battery from AZ and if it doesn't work just return it?

I don't know store policies on batteries.

[Lucky1]

Originally Posted by Kev312

Might be a dumb question but, can I grab a battery from AZ and if it doesn't work just return it?

I don't know store policies on batteries.

What year is your car? Wasn't there a recall for the power cable run from the battery to the rest of the accessories which could cause the car to turn off while driving? Has that issue been addressed on the car and could that be a factor here?

[Kev312]

It's a 2008. I'm not sure about the recall, the only recall I remember receiving was for the Takata airbag deploying metal fragments. However, I do know the instance you're talking about affecting others. Never had any issues with the car turning off or power issues in the past other than replacing the OEM battery about a year and a half ago.

It's an autotragic too if that makes any difference.

[Lucky1]

Originally Posted by Kev312

It's a 2008. I'm not sure about the recall, the only recall I remember receiving was for the Takata airbag deploying metal fragments. However, I do know the instance you're talking about affecting others. Never had any issues with the car turning off or power issues in the past other than replacing the OEM battery about a year and a half ago.

It's an autotragic too if that makes any difference.

Do the electronics work but it just won't turn over? Maybe a starter or alternator issue then?

If the electronics don't work is there a way to test from the terminals in the hood whether they're seeing voltage there?

Also curious if you're on the original battery. Remember seeing some instances where the battery read good but still didn't have enough cranking power under load to start the car. You have to test the battery under load, just testing by putting a metre on the battery at idle isn't enough. If its original battery its time for replacement soon anyway and amazed you made it this long. Doesn't explain why a jump didn't work unless its really far along though?

[Kev312]

Originally Posted by Lucky1

Do the electronics work but it just won't turn over? Maybe a starter or alternator issue then?

If the electronics don't work is there a way to test from the terminals in the hood whether they're seeing voltage there?

Also curious if you're on the original battery. Remember seeing some instances where the battery read good but still didn't have enough cranking power under load to start the car. You have to test the battery under load, just testing by putting a metre on the battery at idle isn't enough. If its original battery its time for replacement soon anyway and amazed you made it this long. Doesn't explain why a jump didn't work unless its really far along though?

All electronics work, radio, windows, headlights, etc.

I'm going to run it for codes and check the starter and starter relay in a couple hours. The battery is only about a year and a half old because I had to change out the OEM due to poor starting power. Replaced the battery and it's been great ever since, until yesterday morning.

[Southjersey128]

Kind of sounds like a starter to me. If it won't crank with a jump box, thats probably what it is. Try tapping on the starter with a socket extension or something similar. Might get 1 more start out of it.

[Bimmer-Bob]

Originally Posted by Kev312

It's a 2008. I'm not sure about the recall, the only recall I remember receiving was for the Takata airbag deploying metal fragments. However, I do know the instance you're talking about affecting others. Never had any issues with the car turning off or power issues in the past other than replacing the OEM battery about a year and a half ago.

It's an autotragic too if that makes any difference.

Have you had the car since new? Have you tried running the VIN through BMW's Safety Recalls page? Just FYI, a 128i should have been through at least four recall campaigns that I can think of, off the top of my head:

1. Removal of excess B-pillar insulation (considered potentially combustible by the pyrotechnic seatbelt pretensioners in the event of an accident)
2. Something about the positive battery cable where it attaches at the power distribution box behind the glovebox (a few were coming loose and causing cars to stall).
3. VANOS attachment bolts need replacing - the heads of the original fasteners were becoming sheared off (there's a recent thread about this w/ pics).
4. And, of course, the Takata airbag recall.

[Kev312]

Originally Posted by Southjersey128

Kind of sounds like a starter to me. If it won't crank with a jump box, thats probably what it is. Try tapping on the starter with a socket extension or something similar. Might get 1 more start out of it.

Gonna give that a shot today, was lazy nearing the end of last week and took a short trip over the weekend so didn't work on the car at all. Gonna knock on the starter today and see if it will attempt to turn. If not, on to the next.

Originally Posted by Bimmer-Bob

Have you had the car since new? Have you tried running the VIN through BMW's Safety Recalls page? Just FYI, a 128i should have been through at least four recall campaigns that I can think of, off the top of my head:

1. Removal of excess B-pillar insulation (considered potentially combustible by the pyrotechnic seatbelt pretensioners in the event of an accident)
2. Something about the positive battery cable where it attaches at the power distribution box behind the glovebox (a few were coming loose and causing cars to stall).
3. VANOS attachment bolts need replacing - the heads of the original fasteners were becoming sheared off (there's a recent thread about this w/ pics).
4. And, of course, the Takata airbag recall.

I have not had the car since new. Purchased about 5 years ago with 50,000 miles, it is now about to turn 180,000 miles. Up until this point it's only needed basic wear and tear maintenance, really been a great reliable car.

I'll definitely check on the battery cable, but the car has never stalled. It's struggled to start in the past, but the OEM battery had just gotten old. Threw a new one in and all was well. Appreciate your input.