Intermittent Starting Issue

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brotherhay
Posts: 66
Joined: Fri Apr 17, 2009 11:40 am

Intermittent Starting Issue

Post by brotherhay »

For years I have been having the same starting issue. Im not sure why, but sometimes the car just will not start. Ill get it started randomly, drive it around, see the alternator charging and all seems well. I can sometimes shut if off, let it sit and start it right back up. This has just happened to me again today. I pulled the car out of storage, charged the battery and it started right up. Let it run, it was charging, all is good. Shut it down, let it sit, fired it right back up, cool. Left for a bit, came back fired right up again cool!

Drove it home, parked it and let it idle for a bit while I messed with the fan/AC/Windows and such. Shut the car off and went to put the cover on it. I noticed a back window was slightly down still so I went to fire up the car and nothing. I get all the Accessory lights on, and all seems good except nothing to the starter or the solenoid isnt engaging, something. Sometimes when this happens, I can hold the key in the start position, and after some time (seconds) it will actually engage. Almost seems like it could even be the ignition switch.

I have replaced the alternator, starter, the ground strap. All these things work when juice gets applied properly. But thats the problem, sometimes it seems turning the key just is not doing what is expected of it. Any ideas or help is appreciated. This car needs to be driven so much more, but I cannot trust it at all if it just randomly will not start
gmonsen
Posts: 87
Joined: Tue Mar 30, 2021 1:06 pm

Re: Intermittent Starting Issue

Post by gmonsen »

Is it possible that the ignition switch itself is bad? I had the same issue with my 1990 Corvette ZR1. It was the ignition switch.
brotherhay
Posts: 66
Joined: Fri Apr 17, 2009 11:40 am

Re: Intermittent Starting Issue

Post by brotherhay »

Quite honestly, it seems is has to be something like that. Ive replaced everything under the hood thats even remotely related to starting the car. I will try and check schematics, but I thought there might also be some sort of starting relay under the knee kick panel on the drivers side. Ive seen a few there, but before I get stupid Ill check into schematics.

But yes, I do believe it is time I started testing the ignition switch. Any quick and easy ways? It would definitely be the Start portion of the ignition. Accessories/On has always worked.
brotherhay
Posts: 66
Joined: Fri Apr 17, 2009 11:40 am

Re: Intermittent Starting Issue

Post by brotherhay »

Now that I think about this, the whole column comes out pretty easily. I never had it all the way out, but I have dropped it down to get the cluster out more than a few times. Geez, now im wondering, this could be simple as a bad spade connection at the end of the ignition harness.

I will most likely pull the whole column out and test it on the bench.
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Mike W.
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Location: Sonoma County

Re: Intermittent Starting Issue

Post by Mike W. »

The ignition switch is my first thought, but not the only one. What exactly are the symptoms? Is it an A/T? I've seen more bad intermittent neutral safety switches than ignition switches. The battery is a possibility, I saw one with an intermittent dead cell one time where it would test out at 12V, but sometimes only 10 volts. Does it try to start at all or just nothing? Any clicks? Do the headlights work and brightly when this happens?
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
brotherhay
Posts: 66
Joined: Fri Apr 17, 2009 11:40 am

Re: Intermittent Starting Issue

Post by brotherhay »

I went to move it this morning after sitting for 3 days, fired right up....

its an automatic transmission, so the safety switch is a strong possibility. I do believe, but need to double check, that when I try and start the car the lights dim on the cluster, and I have to think the headlights do also. I will confirm that next time it fails though.

Im sure it will act up again, but when the problem happens, there is no audible solenoid click or any click for that matter. One noticeable tidbit is if I hold the key in the start position for any random length of time, be it 5 seconds or longer, sometimes it will actually make connection and turn. Ive also noticed when a successful start happens, sometimes there is a very slight delay of half a second or less from the key being fully engaged until the starter starts to turn over.


The battery is new as of last year. It was also topped off with a charge prior to moving it. it was holding 12.76v at the time. A newly refurbed alternator was installed and tested after starting it for the first time after sitting for months. It was pushing a steady 13.85v to the battery while the car was running.
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Mike W.
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Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: Intermittent Starting Issue

Post by Mike W. »

On light brightness what I mean is sometimes the battery cable terminals won't be making great contact, but enough for little things, but when something like the starter or even headlights are used it will drop to nothing.

On the neutral safety switch, I've rehabbed at least one of them by just spraying contact cleaner into the opening and working it back and forth. A little hard to see but the slot is on the left in this picture, though more or less pointing up when installed.

Image
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
brotherhay
Posts: 66
Joined: Fri Apr 17, 2009 11:40 am

Re: Intermittent Starting Issue

Post by brotherhay »

I looked into purchasing one of those last night, then found one on ebay, NOS for $40 shipped so why not I guess.

I am really leaning towards the safety switch myself. When investigating the part, I also notice something that I think is missing with my gear lever. Theres no button underneath. I had no idea there was even supposed to be one until checking the parts list. I just slide it into gear and leave it at that. Yup, leaning towards safety switch....
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Mike W.
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Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: Intermittent Starting Issue

Post by Mike W. »

Oops, the open slot is on the right, not the left in the pic. The neutral switch can be distinctly intermittent, it really would be my first guess. Sometimes wiggling it back and forth will help or moving it down to the neutral position rather than park.

On the locking button you're probably just missing the spring although it could be the button too.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
brotherhay
Posts: 66
Joined: Fri Apr 17, 2009 11:40 am

Re: Intermittent Starting Issue

Post by brotherhay »

Ok so here we go, maybe, hopefully?

Spent some time on the car today and replaced the Neutral Safety Switch. Not too much of a pain, but do not forget to replace the spring for the shifter button before you reassemble it.... So I got that in, with a new spring, and all cleaned up. I was listening to the radio and the battery was at 12.23v. Turn the key, nothing. I put a solar charger on there and boost it to 12.76v and bingo, it turns over.

Thinking thats great, I let it run a bit to charge up, then shut it off and covered it back up. After about 5 minutes of thinking I thought to myself, I should just take it for a rip, really clean stuff up and charge that battery more. I go back out, turn the key, nothing...I put the charger on it just hoping its low volts but at 12.5v, nothing. 12.6v nothing, 12.7 like before, still nothing.

I can see with the key turn, the lights are dimming, and the multimeter is showing a big hit, as if it wants to turn, but just is a bad connection, something. I think to myself all thats left is the ignition, so lets get the column out, see whats up. I pull the knee kick out, and see all the connections. Theres 3 large harnesses coming out of it, and one has a black end that you can see has a huge hot lead. Gotta be the ignition. I pull that out, nothing looks like it got hot ever, minor powdery corrosion. I plug it back together, wiggled it, pulled it apart, and back together again. Turn the key, it starts.....

Ill double check those connections, but Im guessing a bit of dielectric on the ends and that is the final solution to this problem. It would explain a few things, namely the intermittence.

The safety switch I pulled out of there, lol. I mean if that did work, its amazing. It was so gritty and full of dog hair and whatever, wow. Getting that and the spring replaced is great. The rod was not making contact with the plastic gear map thing at all.

I will be testing this car in intervals of days. I am metering voltage drop just to see if everything is buttoned up so it will be some time before I return with results. Typically with this previous problem it did not take long to see the failure return. Thanks for the help, in advance.
brotherhay
Posts: 66
Joined: Fri Apr 17, 2009 11:40 am

Re: Intermittent Starting Issue

Post by brotherhay »

Battery settled to 12.45v on Sunday evening. Wednesday evening the voltage was 12.19v. Seems a little more drain than usual, but Ill figure that out if needed later. I turn the key and it starts. Let it run for a bit to charge the car back up some. Shut if off and let it settle down again, this time to 12.40v.

Tried the key again for good measure, and it turns. Only time will truly tell, but I do feel pretty confident about the connection at the end of the ignition switch. I removed the harness to take a good look at each female end and noticed whatever the purple wire was had lost its position in the harness connector and had slid back in position some. I peeled it all the way out, bent the tab and shoved it back in. I hit each socket with just a touch of dielectric and buttoned it back up.

Anyone know what the purple wire coming out if the ignition harness is for? It was the only suspect connection that was visible. it was easily pushed back half the spade length.
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