starts - won't run unless key held

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garyinwestoz
Posts: 390
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
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starts - won't run unless key held

Post by garyinwestoz »

This 80' 528i I have has been running fine, test driving up and down the street ( not yet registered)
I recently reset the valve clearances.

then the other day I go to move it and - starts + runs 2- 3 sec ( cold start injector working) but then cuts off. If key is held on stays running.

I've ;
changed combo relays - same result
swapped AFM - same result
added some fuel (9 ltrs) - fuel pump is gurgling when AFM trap is opened

its seems either- fuel is being shut off to injectors,
- or power to sparks plugs or
- its do with the key ignition barrel.

Any thoughts on where to look next, or test I can do
chow
Gary
74 525 auto
76 525 - 4 speed, LPG and holley carb- restoring
77 528i- 4 speed manual
77 528i -4 speed manual getting rusty
79 528i auto - a SA car?
80 528i auto - ready to relicense
81 528i +3.5ltr - auto - restoring
86 525e 5 speed manual- dd
garyinwestoz
Posts: 390
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
Contact:

Re: starts - won't run unless key held

Post by garyinwestoz »

10 minutes later
removed dash below steering column, removed steering column cover - oh dear back of ignition barrel is loose. hold firm , turn key, starts - and stays running when take hand off key!

LOL

hope thats all it was

hmm seem to have a intermittent backfire - best relook at tappets!

chow
Gary
74 525 auto
76 525 - 4 speed, LPG and holley carb- restoring
77 528i- 4 speed manual
77 528i -4 speed manual getting rusty
79 528i auto - a SA car?
80 528i auto - ready to relicense
81 528i +3.5ltr - auto - restoring
86 525e 5 speed manual- dd
garyinwestoz
Posts: 390
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
Contact:

Re: starts - won't run unless key held

Post by garyinwestoz »

call it bad luck or stupid dunno
I asked my wife to help me get the lead out ( smaller mor gentle hands), well bugger me it broke!

Here are the parts removed - any idea how it goes back togather - is there a drawing anywhere?

thanks in advance
Gary

Image

https://lh3.googleusercontent.com/qKTpC ... 75-h731-no
Last edited by garyinwestoz on Mon Oct 29, 2018 11:17 pm, edited 1 time in total.
74 525 auto
76 525 - 4 speed, LPG and holley carb- restoring
77 528i- 4 speed manual
77 528i -4 speed manual getting rusty
79 528i auto - a SA car?
80 528i auto - ready to relicense
81 528i +3.5ltr - auto - restoring
86 525e 5 speed manual- dd
User avatar
528i-1981
Posts: 557
Joined: Wed Feb 07, 2018 5:50 am
Location: Franklin, TN

Re: starts - won't run unless key held

Post by 528i-1981 »

Hi Gary - your photo didn't make it, at least not on my computer, but maybe page 61-13 will help:
https://www.bmwtechinfo.com/repair/main/057en/index.htm
(oo=00=oo) Eric
1981 528i Manual
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RandyM
Posts: 95
Joined: Fri Jul 16, 2010 4:01 pm
Location: Ojai, Ca

Re: starts - won't run unless key held

Post by RandyM »

Your photo doesn't appear. Sounds like fuel pump is not getting power in run mode.
Maybe this is what you're looking for: https://www.realoem.com/bmw/enUS/showpa ... Id=32_0499
When I had a similar problem I replaced the wire harness, #2 in diagram, did not solve problem. Apparently the interface between key lock cylinder and electrical contacts cap wears out, difficult to remove lock cylinder, involving removal of 4 anti-theft bolts to allow lock cylinder replacement.

That tiny grub screw, #11 is what holds the cap on, flat head screwdriver.
1981 Sapphire blue automatic
Hit 200k mi. on Fathers Day 2016!
250k October 2020
Family owned since new
Route 150 between Ojai and Santa Barbara
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Mike W.
Posts: 2782
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: starts - won't run unless key held

Post by Mike W. »

You need to host the pic somewhere else like https://imgur.com/

Sounds like you need a new ignition switch though. It comes out, you might think it doesn't, but it does, just a tight fit. Originally there was a little tiny slotted screw with paint on it that held it in place. Somewhere between cheap and expensive, I'm seeing ~$70.

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
garyinwestoz
Posts: 390
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
Contact:

Re: starts - won't run unless key held

Post by garyinwestoz »

yep Mike thats the cable - although I have the metal housing.

parts I have now are 4 small springs, 2 brass/copper plates

I got it back together and held it tight, reconnected and car started - so its this switch.

Image
74 525 auto
76 525 - 4 speed, LPG and holley carb- restoring
77 528i- 4 speed manual
77 528i -4 speed manual getting rusty
79 528i auto - a SA car?
80 528i auto - ready to relicense
81 528i +3.5ltr - auto - restoring
86 525e 5 speed manual- dd
garyinwestoz
Posts: 390
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
Contact:

Re: starts - won't run unless key held

Post by garyinwestoz »

Well, I've tried to put this switch back together - not working to well- either I've got it wrong or the parts are too warn to get electrical contact

getting dash lights, but no power to starter

I did get to work out how to by pass at the plug - connect blacktop green - for continuous power and then red to black to start.

any recommendation on where to get a new switch /cable.
so far I've found
$85 US blunt tech

https://blunttech.com/products/13026188

$89 US auto zone
https://www.autozone.com/batteries-star ... 315385_0_0

$102 US AutohausAZ
https://www.autohausaz.com/pn/32321150466

140 Euro Wallothnesche
https://www.wallothnesch.com/en/ignitio ... 37-02.html
74 525 auto
76 525 - 4 speed, LPG and holley carb- restoring
77 528i- 4 speed manual
77 528i -4 speed manual getting rusty
79 528i auto - a SA car?
80 528i auto - ready to relicense
81 528i +3.5ltr - auto - restoring
86 525e 5 speed manual- dd
User avatar
Mike W.
Posts: 2782
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: starts - won't run unless key held

Post by Mike W. »

I swear it's more expensive than when I looked 2 weeks ago, I'm not seeing anything cheaper than what you've found.
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
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