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mjshira mjshira is offline
Sports Purpose 911 Driver
 
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Join Date: Mar 2002
Location: La Jolla, CA
Posts: 4,368
Quote:
Originally Posted by bazar01 View Post
We should tackle your no-spark issue first.
Check for proper power supplies and ground points on the DME computer plug.
Pin 18 - you should see +12V batt all the time.
Pin 37 - this is switched +12V coming from DME relay pin 87. (ignition ON)
Pins 2, 18 & 24 are all ground points. Use a meter set to ohms. Should be less than 0.2 Ohm. Put one probe on the DME pin and other probe on chassis ground.
did you mean to mention pin 18 twice?

I can tell you already, that I don't have power @ pin 37 with the key on. The only way to get power to position 37 was to jumper the DME relay at the fuse panel. I did this, but even when done, the car won't start. But I did hear the fuel pump running. I think, if I understand the DME relay function enough, that if any of the three grounds at the DME relay (the smaller blades on the relay) are not good then the DME relay wouldn't perform its full function and the car wouldn't start.

The DME relay is good, I have three functional DME relays and I've tested all of them with the same result.

So keeping in mind that this all started when I removed the DME itself and changed the chip, I think a ground was disturbed 'somehow' during that process. I am just not sure 'where' or 'how'.

does that make any sense?
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James Shira R Gruppe # 271
1972 911 Coupe 3.8 RS ‘nbr two’
1972 911 Coupe 3.2 TwinPlug MFI 'Tangerina-Jolie'
1955 356 Pre A Coupe ‘old red’
1956 356A Emory speedster build in progress
Old 11-12-2007, 10:22 AM
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