Weekend FI fun.

[jadney@vwtype3.org (Melissa & Jim)]

>From: Jason Renville <Jason_Renville@ccm.al.intel.com>

>        You may remember I was asking about the trigger contacts on a 69 
>     fastback.  I had a chance to work on it and I wanted to share my 
>     results so everyone might gain a little???  
>     
>        I will start off with the problem:  
>        I was only firing on two cylinders at an idle.  When I opened the 
>     throttle I would begin firing on all cylinders about 2000 rpm.
>        
>        I checked for spark and found it at all cylinders.
>        
>        Using Muir's test I tested the trigger contacts.  One ohm when 
>     closed and infinite when open on one set.  Seventy-five ohms when 
>     closed infinite when open.
>     
>     
>     Solution:
>        I removed the trigger contacts and noticed a type of oxidation on 
>     one set of contacts.  I used an Exacto(R) knife to scrape off the film 
>     and then proceeded to reinstall the contacts.  
>     
>     Result:
>        She fires on all four cylinders at an idle.  Don't have to keep the 
>     pedal pushed down a little to keep it running.
>                                Jason Renville

This is interesting.  I have never seen a failure that was other than 
infinite resistance (dirt!) and this always results in a completely 
non-running engine.  I realize that this is counterintuitive, but that is 
all I have seen.

It had never occurred to me to wonder what happens if the failure mode is at 
some intermediate resistance.

Anyone else ever seen this?

Jim
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       Melissa Kepner                                    Jim Adney
       jadney@vwtype3.org              jadney@vwtype3.org
                             Laura Kepner-Adney
                             Madison, Wisconsin
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