[DeTomaso] Engine run after switching off ignition

[Thomas Tornblom]

Dave Londry skrev:
> I have this same problem Thomas.
> MSD ignition,
> Fans not spinning,
> All autometer gauges,
> No alternator idiot lamp.

I assume you still have the resistor that is needed to get the 
alternator magnetized on startup. It is connected in parallel with the 
idiot lamp and I'm fairly certain that this is the problem.

I hope I'll have time to have a go at a fix over the weekend.

Cheers,
Thomas

> 
> So I really want to hear about your results.
> dave
> 
> Thomas Tornblom wrote:
>> Larry - Ohio Time Corp skrev:
>>   
>>> Thomas,
>>>
>>> Please remember that the cooling fans have been known to cause this problem
>>> as they spin down. They generate enough power to keep things running.
>>>     
>>
>> I know, but I have fixed my fan setup so that it is not vulnerable to 
>> this. The fan wasn't running either.
>>
>> Thanks for the suggestion though.
>>
>> I do believe I know where I should install the diode as I said in the 
>> response to Charlie.
>>
>> I will most likely have to modify the tacho anyway as the tacho signal 
>> from the EDIS system is of much lower amplitude than from the TFI system.
>>
>>   
>>> Larry - Cleveland
>>>     
>>
>> Cheers,
>> Thomas
>>
>>   
>>> -----Original Message-----
>>> From: detomaso-bounces at realbig.com [mailto:detomaso-bounces at realbig.com] On
>>> Behalf Of Thomas Tornblom
>>> Sent: Friday, April 24, 2009 2:48 AM
>>> To: DetomasoList
>>> Subject: [DeTomaso] Engine run after switching off ignition
>>>
>>> I fired the engine up last night for the first time after upgrading from 
>>> TFI to EDIS (Ford crank trigger). This is nice as I will finally be able 
>>> to get rid of the large cap distributor, which sits too close to the 
>>> firewall for the engine cover to fit properly.
>>>
>>> One unanticipated problem is that the engine now runs after I switch off 
>>> the key :-| It stops if I press the brake pedal with the ignition off.
>>>
>>> Looking at the diagrams it appears that the TFI module and single coil 
>>> was fed directly from switched power, while the EDIS module and quad 
>>> coils are fed through the EFI power relay, so now the current drawn from 
>>> switched power is just the hold current for the relay, while it used to 
>>> also be the current for the TFI and coil.
>>>
>>> I assume the problem is with the alternator idiot lamp circuitry, which 
>>> feeds current from the spinning alternator backwards and keeps the relay 
>>> engaged.
>>>
>>> IIRC this has been a problem also for some who installs MSD ignitions 
>>> and that it is probably solved by installing a diode somewhere in the 
>>> idiot light cuircuit.
>>>
>>> Anyone have any info on what the simplest solution is?
>>>
>>> Cheers,
>>> Thomas
>>>
>>>     
>>
>>
>>   
> 
> !DSPAM:49f1f005204652974427724!


-- 
Real life:   Thomas Törnblom             Email:  Thomas.Tornblom at Hax.SE
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