Quote:
| Originally Posted by Ray the tacho could be made to go to zero by putting the battery under load with the lights on full beam. |
Had a similar experience with my 998 about a year ago. Tacho would occasionally drop to zero, or "flutter" wildly, with the problem appearing more frequently when lights were on. When I put it in to get fixed, two problems were discovered.
1. I had a slight misfire - didn't even feel it - that was due to some faulty alarm-related wiring.
2. The tacho problem was traced to the ECU. Fortunately, I still had the original ECU (it had been replaced as part of an engine upgrade) and when this was put back in it sorted the problem.