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 Post subject: Damn car still wont f***ing start!!!!!!!
PostPosted: Wed Sep 09, 2009 3:36 pm 
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Posts: 67
Been having issues with my 85 lux now for a few weeks. Ran fine for a while but then one day just wouldnt start after running fine all day.
Left it for a day or two then it started fine. Stopped at the garage and it wouldnt start again. Ended up having to get the AA out who also couldnt get it going.
Ive done all the checks, swapped the DME relay, got fuel, initially had a spark but now have no spark, power to the coil, all fuses/relays are good.
There was no bounce at the tach so replaced the speed/ref sensor today and still it wont go.
Im starting to suspect the DME brain now.
Im losing patience with it as well now and im about to get the sledge hammer out and give it a good thrashing!!!!!!
:evil: :evil:
shaun


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 Post subject: Re: Damn car still wont f***ing start!!!!!!!
PostPosted: Wed Sep 09, 2009 6:10 pm 
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Joined: Thu Dec 13, 2007 8:33 pm
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Location: Wolverhampton
Sounds like it could be the cam sensor.


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 Post subject: Re: Damn car still wont f***ing start!!!!!!!
PostPosted: Wed Sep 09, 2009 6:18 pm 
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Joined: Sun Nov 04, 2007 7:43 pm
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Location: Chatham, Kent
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OK you have no spark yes/no? Does the tacho bounce now you changed the sensor? Is the voltage on the coil swinging as it turns over?
Have you checked for a spark on the output of the coil?

Are the injectors triggering? Is there fuel on the injector rail?

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 Post subject: Re: Damn car still wont f***ing start!!!!!!!
PostPosted: Wed Sep 09, 2009 6:41 pm 
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Ok to clarify. There is no spark at the plugs and no spark at the coil end.
There is still no bounce at the tach.
There is fluctuating voltage at the coil when its turned over but deffo no spark.
There is fuel at the rail.
I have even tapped the DME brain as suggested on the clarks website with a mallet to see if it will fire intermittently but still no joy.
Its had new dizzy cap and rotar arm and new plugs that are gapped correctly.
Im runnin short of ideas and if i could lay my hands on a spare DME brain i could change that so i could at least rule it in or out.


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 Post subject: Re: Damn car still wont f***ing start!!!!!!!
PostPosted: Wed Sep 09, 2009 7:02 pm 
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Joined: Thu Nov 15, 2007 6:44 pm
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Location: Towcester, Northants
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If you have a switching voltage at the coil and no spark your problem must be the coil.

You should have a permanent 12v feed to one side of the coil and the other side will be a switched 0V. Put a dvm across the coil turn the car over and you should see 12v 0v 12v etc - if you have a good meter.

Rich


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 Post subject: Re: Damn car still wont f***ing start!!!!!!!
PostPosted: Wed Sep 09, 2009 7:21 pm 
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But would that explain no bounce at the tach?


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 Post subject: Re: Damn car still wont f***ing start!!!!!!!
PostPosted: Wed Sep 09, 2009 7:31 pm 
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Location: Towcester, Northants
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No it wouldnt.

Reading back you've changed the ref sensors - did you put them to the correct height? they must be a set distance from the flywheel.

Did you measure the coil voltage correctly?

Rich


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 Post subject: Re: Damn car still wont f***ing start!!!!!!!
PostPosted: Wed Sep 09, 2009 7:56 pm 
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I changed the ref/speed sensors and i assume the height is correct as i slid them both out and left the original mounting brackets in place and the replacement sensors were like for like.
As for the coil voltage i went by the specs in the haynes manual.
Thats what makes me think its the DME brain as everything else adds up???????????/


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 Post subject: Re: Damn car still wont f***ing start!!!!!!!
PostPosted: Thu Sep 10, 2009 7:37 pm 
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Joined: Mon Nov 05, 2007 6:24 pm
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Location: Halifax
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The sensors arn't always the same length. They will need setting up correctly. Read up clarks.

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Audi 2.0 TDI Good but rather boring..........
944 now sold.


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 Post subject: Re: Damn car still wont f***ing start!!!!!!!
PostPosted: Fri Sep 11, 2009 10:16 am 
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Joined: Tue Sep 02, 2008 2:03 pm
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Location: Midlands
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I have a DME and AFM in the for sale section for an early 944 :wink:

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 Post subject: Re: Damn car still wont f***ing start!!!!!!!
PostPosted: Fri Sep 11, 2009 4:53 pm 
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Cheers daz, how much for just the DME and where in the midlands are you?
shaun


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 Post subject: Re: Damn car still wont f***ing start!!!!!!!
PostPosted: Fri Sep 11, 2009 7:38 pm 
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Location: Halifax
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Got a spare DME you can have for free. Just PM me your address.

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944 lux, Eco car. Off the road more than it's on!
Audi 2.0 TDI Good but rather boring..........
944 now sold.


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 Post subject: Re: Damn car still wont f***ing start!!!!!!!
PostPosted: Sat Sep 12, 2009 6:33 pm 
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im having the exact same issues on my 83 944! arghhhhhh


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 Post subject: Re: Damn car still wont f***ing start!!!!!!!
PostPosted: Sat Sep 12, 2009 6:34 pm 
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what and where are these reference sensors you talk of and what is the rev counter bounce all about?


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 Post subject: Re: Damn car still wont f***ing start!!!!!!!
PostPosted: Sun Sep 13, 2009 10:29 am 
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Joined: Sat Mar 01, 2008 10:00 am
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Location: Mid Sussex
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deacs wrote:
what and where are these reference sensors you talk of and what is the rev counter bounce all about?


The flywheel sensors are at the back of the engine block. Low down on the passenger side. There are two of them held in by allen bolts. You have to lean in and get down just behind the oil filler to be able to remove them.
Mine's had the same problem before and I think is suffering again.

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