starts - won't run unless key held

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garyinwestoz
Posts: 108
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 » Fri Oct 26, 2018 10:00 pm

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
77 528i -4 speed manual getting rusty
76 525 - 4 speed manual LPG and holley carb
81 528i - auto - to be relicensed with a 3.5 (83 735i)
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual

garyinwestoz
Posts: 108
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
Contact:

Re: starts - won't run unless key held

Post by garyinwestoz » Fri Oct 26, 2018 10:09 pm

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
77 528i -4 speed manual getting rusty
76 525 - 4 speed manual LPG and holley carb
81 528i - auto - to be relicensed with a 3.5 (83 735i)
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual

garyinwestoz
Posts: 108
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
Contact:

Re: starts - won't run unless key held

Post by garyinwestoz » Fri Oct 26, 2018 11:23 pm

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.
77 528i -4 speed manual getting rusty
76 525 - 4 speed manual LPG and holley carb
81 528i - auto - to be relicensed with a 3.5 (83 735i)
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual

User avatar
528i-1981
Posts: 68
Joined: Wed Feb 07, 2018 5:50 am
Location: Boston North Shore, MA

Re: starts - won't run unless key held

Post by 528i-1981 » Sat Oct 27, 2018 7:32 am

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 5-speed

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RandyM
Posts: 89
Joined: Fri Jul 16, 2010 4:01 pm
Location: Ojai, Ca

Re: starts - won't run unless key held

Post by RandyM » Sat Oct 27, 2018 1:21 pm

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!
Family owned since new
Route 150 between Ojai and Santa Barbara

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Mike W.
Posts: 2381
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: starts - won't run unless key held

Post by Mike W. » Sun Oct 28, 2018 3:33 pm

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: 108
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
Contact:

Re: starts - won't run unless key held

Post by garyinwestoz » Mon Oct 29, 2018 11:35 pm

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
77 528i -4 speed manual getting rusty
76 525 - 4 speed manual LPG and holley carb
81 528i - auto - to be relicensed with a 3.5 (83 735i)
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual

garyinwestoz
Posts: 108
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
Contact:

Re: starts - won't run unless key held

Post by garyinwestoz » Wed Nov 07, 2018 8:33 pm

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
77 528i -4 speed manual getting rusty
76 525 - 4 speed manual LPG and holley carb
81 528i - auto - to be relicensed with a 3.5 (83 735i)
79 SA ? 528i auto
79 528i auto parts car
86 525e 5 speed manual

User avatar
Mike W.
Posts: 2381
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: starts - won't run unless key held

Post by Mike W. » Thu Nov 08, 2018 1:10 pm

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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