1985 Porsche 944 no tail lights and the tach guage and MPG

1985 PORSCHE 944
14,200 MILES • 4 CYL • 2WD • MANUAL
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KHRISTINE HUMPAL
  • MEMBER
  • 1 POST
We bought this car drove it about 100 miles it sputtered and died. We replaced the ecm it started right up. It started charging at 17V we replaced the alternator and it runs fine. I have no tail lights, the tach and MPG guage constantly jumps at idle. It goes to zero then jumps.
Sep 22, 2009 at 7:57 PM
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MIKE H R
  • CAR REPAIR CONTRIBUTOR
  • 3,094 POSTS
When you changed the ecm did you disconnect the battery? If not disconnect the negative side of the battery and with it off check all the connections {grounds, } not only around the battery but the rest of the car. the tail light could have blown a fuse and with the tach and mpg acting up it sounds like a bad ground or a loose wire. Some wires look clean in reference to a ground but underneith there could be getting a bad contact. I do not think it is in the ecm as the lighting system runs on its own line
Sep 23, 2009 at 9:56 AM
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