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flooded 79 635?

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ldc
Posts: 24
Joined: Wed May 16, 2018 3:01 pm
Location: Fredericksburg TX

flooded 79 635?

Post by ldc » Thu Jul 19, 2018 9:05 pm

I am not sure what is wrong. I started the car in the garage and backed it out 20'. tinkered with it for 30 minutes and it cranks but no spark. I am new to the BMW and fuel injection thing. All of my old cars have been carbs so......

Can I wait a while and it will dry out? how long do you think it would take? I don't want to try again and re-flood it - if that is in fact the problem.

I was recently gone for a couple weeks and came home and the battery was dead but I put it on a charger and it started right up so I don't think it is related to that.

I haven't had the car for long but it usually starts right up.

Any hints appreciated.

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Brucey
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Location: Cambridge, UK

Re: flooded 79 635?

Post by Brucey » Thu Jul 19, 2018 10:03 pm

you have L-jet, right? The ways of this system are arcane to say the least.

Crank but no spark on this type of EFi system usually means

- no power to ignition (eg dodgy relay)
- no 'start signal' to ECU (applies to motronic but perhaps not L-jet)
- dodgy pulse generator to create spark signals (in distributor on L-jet)
- dodgy ignition amplifier
- dodgy 'mapped ignition' ECU (some l-jet versions)

The best online resource for L-jet systems of the type that are used on early E24 is probably the 'firstfives' website.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Pod
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Location: usually in the barn, Kent, England.

Re: flooded 79 635?

Post by Pod » Thu Jul 19, 2018 10:53 pm

You said you “tinkered” with it. If this “tinkering” involved the engine or electrics, then I suggest you recall what you did and start there - maybe try to reverse what you did!

ldc
Posts: 24
Joined: Wed May 16, 2018 3:01 pm
Location: Fredericksburg TX

Re: flooded 79 635?

Post by ldc » Thu Jul 19, 2018 11:00 pm

no tinkering with motor - didn't lift the hood. I was messing with the front and back license plates - trying to figure out how i am going to mount a US plate on a euro car

ldc
Posts: 24
Joined: Wed May 16, 2018 3:01 pm
Location: Fredericksburg TX

Re: flooded 79 635?

Post by ldc » Fri Jul 20, 2018 12:49 pm

I did put the charger on again and waited a few hours to try to start it and it fired up. When it didn't start it was turning over. not sure if that means it was flooded or the battery was low but I say flooded.

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Brucey
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Joined: Fri Apr 09, 2004 7:17 am
Location: Cambridge, UK

Re: flooded 79 635?

Post by Brucey » Fri Jul 20, 2018 3:49 pm

if the volts drop below about 9V on cranking (eg with a weak battery), some cars will still have an engine that turns over, but the ignition system produces no sparks.

You checked for spark, right, and saw none? It doesn't matter if there is fuel or not, it ain't gonna start without a spark....

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Pod
Bigcoupe supporter
Posts: 3829
Joined: Tue Mar 16, 2010 8:32 pm
Location: usually in the barn, Kent, England.

Re: flooded 79 635?

Post by Pod » Sat Jul 21, 2018 7:12 am

Try fitting a new battery? Sounds like the one you have is on its way out.

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