[DeTomaso] Engine run after switching off ignition

[Thomas Tornblom]

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
> 


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