[s-cars] No start, no spark - 1987 5KS with NF engine

[djdawson2 at aol.com]

 Before you start throwing parts... check for power at the ignition coil.? The only way you get a spark is by providing power to the coil, and an intermittent ground to release the energy to the distributor.? That ground is supplied through the hall sender in the distributor, which does go bad.

Both of these can be tested using a simple test light.? I would advise you to start there.? Run 2 tests...

1) Hook one side of your test light to the negative post on your battery, the other to the hot side of your ignition coil.? Turn the engine over, and the light should be on constantly.? (If you don't get the light, you have a power supply problem)

2) Hook one side of your test light to the positive post on your battery, the other to the ground side of your ignition coil.? Turn the engine over, and the light should blink as the engine is turned over.? (If the light doesn't blink, then you are not getting a ground signal from the distributor, usually indicating a wiring breal or a hall sender failure)

Let us know...

Dave




 


 

-----Original Message-----
From: Grant Lenahan <glenahan at vfemail.net>
To: Dave C <dconner at gmail.com>
Cc: s-car-list at audifans.com; quattro at audifans.com
Sent: Sun, 19 Apr 2009 3:17 pm
Subject: Re: [s-cars] No start, no spark - 1987 5KS with NF engine










i read twice, quickly. You never mentioned the infamous ignition switch.

Did you swap it? Its largely un testable.

Grant
On Apr 19, 2009, at 4:15 PM, Dave C wrote:

>  <200q20v at audifans.com>
> Folks,
>
> I'm about at the end of my rope in trying to find the cause of this no
> start, no spark problem. This car is a 1987 5KS with NF engine and  
> CIS E-III
>
> The car always ran fine and then began to act up about a few weeks  
> ago...
> failed to start once or twice, but later would start and run as  
> normal. Shut
> it off and maybe it would start again, maybe not. Now for the past  
> couple
> weeks I haven't been able to get it to start at all. I checked for  
> fault
> codes several times and got none ... just 4444. The battery has  
> lots of
> juice and the starter cranks the engine nice and fast.
>
> There is no spark from the coil. I tried various tests as described in
> Bentley ... coil, power stage (ignition booster?), and a few other  
> things. I
> swapped various parts including:
>
> Knock sensor control unit (aka ICU, aka electronic ignition control  
> unit) in
> drivers side footwell
>
> ECU (fuel injection control unit)- in the passenger footwell
>
> Coil incl power stage (ignition booster)
>
> Distributor ... although I don't think that has anything to do with  
> lack of
> spark at the coil
>
> I checked the grounds in the engine compartment, all looked OK,  
> cleaned them
> up anyway.
>
> Checked all wiring connectors at coil, distributor, etc
>
> Examined all related wiring that I can see/identify for obvious  
> signs of
> damage ... all looks OK.
>
> Bentley's test of the ignition coil seems to indicate either a bad  
> ICU, or
> damaged wiring to the ICU. I checked for continuity in the wire  
> between the
> coil and the ICU and it's OK. I swapped the ICU with another one  
> out of a
> car that runs fine and the car still won't start.
>
> The only remaining thing I can think of is a broken/damaged wire  
> somewhere,
> maybe inside the harness. But where to look?
> I'm very close to giving up and having it towed to an Audi specialist.
> Admittedly, I'm not a pro ... it's possible I'm not doing the tests
> correctly, and my wire diagram skills are not the greatest.
> Does anyone have a suggestion re: what I might have missed? A likely
> location for a damaged wire? Anything at all?
> thanks,
>
> David Conner
>
> Columbus,OH
> 87 5KTQ
> 89 100 NF engine
> 87 5KS NF engine
> _______________________________________________
> quattro mailing list
> quattro at audifans.com
> http://www.audifans.com/mailman/listinfo/quattro
> ---
> Watch this space for ads :)



Grant Lenahan
glenahan at vfemail.net
(201) 602-4702 mobile




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