Yet another car not starting thread

Hi guys, my car doesn't crank when I turn the key. Usually when I don't turn my car on for 2-3 days it has trouble starting up. It cranks a little longer then usual, but eventually starts up. I usually don't let it get past 2-3 days. But this past week I haven't driven the car at all (so 6-7 days it's been laying around) and now when I turn the key the engine does not even crank.

I've searched a bit and most people suggested a flat battery and bad fuel pump. My fuel pump is only a few months old so I'm pretty sure it's still good (it also churns when the key is in position 2). I tried boosting the battery but still no good. My voltage is at 12.0 - 12.1 without being connected to another car. And around 13.9 - 14.0 when it is connected to another battery. Those voltages are fine to start up the car right?

What are other common issues that would prevent a car from cranking?

Starter.

trade in a friend's battery after letting it sit for a while and see if that solves it. If not, starter.

Depending on how and where you measure the battery, 12 Volts reading is only about 50% level of charge. A fully charged battery should read 12.6 Volts.

You need to leave your windows and hood open and after you turn off your car, come back after 25 minutes and listen to determine if you can hear any fan motor running. There are 2 fan motors that have issue, the small one in the climate control panel and the main HVAC blower motor.

Doubt your fuel pump is an issue if you have the battery going flat.

This sounds like battery to me too. When jumping, did you connect to terminals under the hood? Also, you should keep the cars hooked up for maybe 5 mins. with donor car revving slightly. Then try to start.

Bet it will...or you could try jump starting.

Check date on battery...if old...it might just be its time.

14v when jumping should be more than enough...you may have to leave the cables connected for longer, though.

Originally Posted by dmax

When jumping, did you connect to terminals under the hood? Also, you should keep the cars hooked up for maybe 5 mins. with donor car revving slightly. Then try to start.

Also worth noting, do NOT leave the donor car running when you try to start yours...it can blow the diodes in their alternator.

Bet it will...or you could try jump starting.

+1, easiest way.

Originally Posted by lcoleman

14v when jumping should be more than enough...you may have to leave the cables connected for longer, though.

Also worth noting, do NOT leave the donor car running when you try to start yours...it can blow the diodes in their alternator.

+1, easiest way.

Never heard of turning off the donor car before. I've probably jumped cars maybe 20 times in my life and never done this.

These are diodes in the voltage regulator?

Originally Posted by jfoj

Depending on how and where you measure the battery, 12 Volts reading is only about 50% level of charge. A fully charged battery should read 12.6 Volts.

You need to leave your windows and hood open and after you turn off your car, come back after 25 minutes and listen to determine if you can hear any fan motor running. There are 2 fan motors that have issue, the small one in the climate control panel and the main HVAC blower motor.

Doubt your fuel pump is an issue if you have the battery going flat.

What are the issues with the fan motor? btw i used the car's hidden functions to check the voltage (ref: )

Originally Posted by dmax

This sounds like battery to me too. When jumping, did you connect to terminals under the hood? Also, you should keep the cars hooked up for maybe 5 mins. with donor car revving slightly. Then try to start.

Bet it will...or you could try jump starting.

Check date on battery...if old...it might just be its time.

I connected it to the battery terminals in my trunk. My car is in the drive way and it's a bit difficult to get another car's hood near the front of mine.

The battery is 2.5 years old, I think it's still good.

Originally Posted by lcoleman

14v when jumping should be more than enough...you may have to leave the cables connected for longer, though.

Also worth noting, do NOT leave the donor car running when you try to start yours...it can blow the diodes in their alternator.

+1, easiest way.

How much longer do i have to leave them connected? Also i thought I was jump starting the car by connecting the battery to another car's battery.

Is it a manual tranny? I just recently had to swap out my clutch pedal switch because I would randomly get a no crank status on my 323. Try another battery, then check starter and go from there.

Originally Posted by xecure

What are the issues with the fan motor? btw i used the car's hidden functions to check the voltage (ref: )

I connected it to the battery terminals in my trunk. My car is in the drive way and it's a bit difficult to get another car's hood near the front of mine.

The battery is 2.5 years old, I think it's still good.


How much longer do i have to leave them connected? Also i thought I was jump starting the car by connecting the battery to another car's battery.

It can be a 'good' battery that's just lost its juice...from too many short drives and not enough long ones.

Make sure the starter cable is tightened (under + terminal).

You do jump start the way you said...though our hood terminals put power closer to the starter.

Leave the cars hooked up a few mins. at least.

dmax, short drives do not cause as much of a problem as you insinuate. Maybe repeatedly starting and moving the car 1 block, but it's not going to kill a battery. And yes, flyback diodes in the alternator. It is just good practice to turn the car off after the donor car's alternator has charged the dead battery up. You generally don't have to rev it up, either...most alternators will deliver enough current at idle. On an older car, it might be worth trying.

I would leave them connected for at least 10 minutes if the engine isn't cranking at all. However, if you're not getting anything after that time, I stand by post #2. You should at a minimum get a "wuh-wuh-wuh" even if the starter spins the engine too slowly because of low voltage.

Under hood or at the battery should not matter--the cables in the car deliver power to start, so obviously they're adequate to deliver current from a live charging system to a dead battery. Still, at the battery is better.

:-( I don't even get a 'wuh wuh wuh' after having the donor car (engine on) connected to mine (in the front) for 10 minutes.

I'm starting to think it may be the starter. It's just that I know this happens when I leave the car around for a few days and a quick boost usually gets her up and running.

Sent from my MB860 using Bimmer App

lcoleman...it's not the short drives, per se. It's many short drives and no long ones.

I've been in many threads where that's the issue. Starting draws the most power, and if drivers are constantly making 5-10 trips in a day, each of short duration, the battery will progressively get weaker and weaker.

I don't know what OP drives like, so just putting it out there in case he hasn't been on a half an hour ride in a month.

I've read that if you hook up to the terminals under the hood, you get more power directly to the starter. You get some power loss going through that 10' of monster cable from the battery. Also, not to beat a dead horse, thinner jumper cables just don't deliver the same power as thicker ones.

If jumping had always gotten it going before, that does sound like it's not the starter.

You driving patterns just may be it, though. You say that if you don't get to it in 2-3 days it's weaker. I believe that a battery can be 2.5 years old and still have a problem...especially if it's in a constantly weak state. If it was the fsr, you'd have a dead battery in a day from what I hear...certainly in 2.

You live in the city, so it's not unreasonable to think that this is all from your driving patterns. I don't know if a battery can be permanently damaged from being in a continually undercharged state...

Next step I'd suggest after you get it started, is to get the battery load tested or replaced. If you got a 49DL, I know you have a prorated warranty still. If not, go back to where you got it and get it tested at least.

When you get it going, either go on a long drive or right to the battery store.

And I'm tl...dr again...but try to lift up the cables on the battery, check ground cable for tightness...look for corrosion...tighten nut under +terminal cap and ground lug. Easy to do and free and you wouldn't be the first with such a basic issue.

It is more likely that the battery has been damaged from being discharged so often, as the plates become sulfated, which increases resistance and lowers capacity. I'm still skeptical about it being flat dead, so that nothing happens even when it is at 12V or 14V with another battery hooked in parallel.

Does it click, or make any noise at all?

Originally Posted by lcoleman

It is more likely that the battery has been damaged from being discharged so often, as the plates become sulfated, which increases resistance and lowers capacity. I'm still skeptical about it being flat dead, so that nothing happens even when it is at 12V or 14V with another battery hooked in parallel.

Does it click, or make any noise at all?

Nope no clicking what so ever. My dash lights up and my radio plays. I even hear my fuel pump churning. But that's it. Not even a slightest bit of cranking of the engine.

Could also be the ign switch, then.

Bump, never got this fixed.

How will I know if it's my starter vs ignition switch?