flooded 79 635?

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

flooded 79 635?

Post by ldc »

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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Re: flooded 79 635?

Post by Brucey »

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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Re: flooded 79 635?

Post by Pod »

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: 37
Joined: Wed May 16, 2018 3:01 pm
Location: Fredericksburg TX

Re: flooded 79 635?

Post by ldc »

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: 37
Joined: Wed May 16, 2018 3:01 pm
Location: Fredericksburg TX

Re: flooded 79 635?

Post by ldc »

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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Re: flooded 79 635?

Post by Brucey »

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
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Re: flooded 79 635?

Post by Pod »

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